Use require instead of assert for error checking in GridFS tests.

[matthewdale]

Summary

Use require.NoError instead of assert.Nil when checking errors in the GridFS integration tests to prevent the test from continuing after an unexpected error.

Background & Motivation

The GridFS tests in the "internal/integration" package will continue after an error and possibly reference uninitialized values, leading to a panic like:

=== RUN   TestGridFS/skipping_download/read_all,_skip_beyond
    gridfs_test.go:77: 
        	Error Trace:	go.mongodb.org\mongo-driver\internal\integration\gridfs_test.go:77
        	            				go.mongodb.org\mongo-driver\internal\integration\mongotest.go:232
        	Error:      	Expected nil, but got: topology.ConnectionError{ConnectionID:"", Wrapped:(*net.OpError)(0xc02b0c8960), init:true, message:"failed to connect to localhost:27017"}
        	Test:       	TestGridFS/skipping_download/read_all,_skip_beyond
        	Messages:   	OpenUploadStream error: connection() error occurred during connection handshake: failed to connect to localhost:27017: dial tcp [::1]:27017: connectex: Only one usage of each socket address (protocol/network address/port) is normally permitted.
        --- FAIL: TestGridFS/skipping_download/read_all,_skip_beyond (0.09s)
panic: runtime error: invalid memory address or nil pointer dereference [recovered]
	panic: runtime error: invalid memory address or nil pointer dereference
[signal 0xc0000005 code=0x0 addr=0x10 pc=0x7ff6d24487f4]
goroutine 419948 [running]:
...
go.mongodb.org/mongo-driver/v2/internal/integration.TestGridFS.func1.1(0xc02ad641c0)
	go.mongodb.org/mongo-driver/internal/integration/gridfs_test.go:79 +0x454
go.mongodb.org/mongo-driver/v2/internal/integration/mtest.(*T).Run.(*T).RunOpts.func1(0xc02b5604e0?)

[Copilot]

Pull Request Overview

This PR replaces assert.Nil calls with require.NoError when checking for errors in the GridFS integration tests to ensure tests fail immediately on unexpected errors rather than continuing execution and potentially panicking on nil pointer dereferences.

• Changes error checking assertions from assert.Nil to require.NoError throughout GridFS tests
• Adds import for the require package
• Updates one assertion from assert.NotNil to assert.Error for consistency with error checking patterns

[mongodb-drivers-pr-bot]

API Change Report

No changes found!

[mongodb-drivers-pr-bot]

🧪 Performance Results

Commit SHA: 085f31f

The following benchmark tests for version 689b8dfbeee2bf00077eb131 had statistically significant changes (i.e., |z-score| > 1.96):

Benchmark	Measurement	% Change	Patch Value	Stable Region	H-Score	Z-Score
BenchmarkMultiFindMany	total_mem_allocs	25.8094	459361.0000	Avg: 365124.5000 Med: 364944.5000 Stdev: 12416.6057	0.9371	7.5896
BenchmarkMultiFindMany	total_bytes_allocated	25.7991	746845464.0000	Avg: 593681280.0000 Med: 593390168.0000 Stdev: 19635635.7607	0.9388	7.8003
BenchmarkMultiFindMany	total_time_seconds	21.5169	1.2717	Avg: 1.0465 Med: 1.0288 Stdev: 0.0780	0.8649	2.8857
BenchmarkSingleFindOneByID	total_mem_allocs	-15.3834	1407404.0000	Avg: 1663270.8324 Med: 1671894.0000 Stdev: 67901.0461	0.8501	-3.7682
BenchmarkSingleFindOneByID	total_bytes_allocated	-14.8574	87609184.0000	Avg: 102897048.6550 Med: 103439320.0000 Stdev: 4124822.9042	0.8477	-3.7063
BenchmarkBSONFullDocumentDecoding	ops_per_second_min	-14.4159	1557.9552	Avg: 1820.3795 Med: 1861.3672 Stdev: 122.7244	0.7580	-2.1383
BenchmarkLargeDocInsertOne	ops_per_second_med	-13.6832	4929.3136	Avg: 5710.7221 Med: 5715.6738 Stdev: 151.1343	0.8970	-5.1703
BenchmarkMultiInsertSmallDocument	total_time_seconds	13.4419	1.2027	Avg: 1.0602 Med: 1.0475 Stdev: 0.0431	0.8498	3.3100
BenchmarkMultiInsertLargeDocument	total_mem_allocs	-12.1221	1575.0000	Avg: 1792.2593 Med: 1841.0000 Stdev: 109.2413	0.7571	-1.9888
BenchmarkSingleRunCommand	total_bytes_allocated	-10.4408	88668728.0000	Avg: 99005724.6118 Med: 99683088.0000 Stdev: 4938260.0207	0.7695	-2.0932
BenchmarkSingleFindOneByID	total_time_seconds	-10.4059	1.0295	Avg: 1.1491 Med: 1.1560 Stdev: 0.0489	0.7734	-2.4451
BenchmarkSingleRunCommand	total_mem_allocs	-10.0578	960917.0000	Avg: 1068372.2706 Med: 1077155.0000 Stdev: 52893.7285	0.7626	-2.0315
BenchmarkSingleRunCommand	ops_per_second_max	-9.5228	7722.7233	Avg: 8535.5455 Med: 8565.9708 Stdev: 189.4695	0.8811	-4.2900
BenchmarkMultiInsertSmallDocument	total_bytes_allocated	6.1395	473492088.0000	Avg: 446103386.5324 Med: 445522384.0000 Stdev: 13768469.1127	0.7466	1.9892
BenchmarkSingleFindOneByID	ops_per_second_med	-6.0959	3867.7538	Avg: 4118.8355 Med: 4140.2553 Stdev: 114.7683	0.7665	-2.1877
BenchmarkSmallDocInsertOne	total_time_seconds	-6.0142	1.1128	Avg: 1.1840 Med: 1.1850 Stdev: 0.0218	0.8330	-3.2660
BenchmarkLargeDocInsertOne	total_time_seconds	5.1477	1.2430	Avg: 1.1822 Med: 1.1821 Stdev: 0.0238	0.7822	2.5604
BenchmarkMultiInsertSmallDocument	ns_per_op	4.7748	6904.0000	Avg: 6589.3681 Med: 6581.5000 Stdev: 151.4937	0.7403	2.0769
BenchmarkSingleFindOneByID	ops_per_second_max	-4.4841	4419.8114	Avg: 4627.3037 Med: 4626.5025 Stdev: 105.8524	0.7360	-1.9602
BenchmarkBSONFullDocumentEncoding	total_mem_allocs	-3.9393	1345485.0000	Avg: 1400661.7412 Med: 1401964.0000 Stdev: 21663.5964	0.7793	-2.5470
BenchmarkBSONFullDocumentEncoding	total_bytes_allocated	-3.9095	233041504.0000	Avg: 242522981.7412 Med: 242696304.0000 Stdev: 3719834.5002	0.7793	-2.5489
BenchmarkBSONFullDocumentEncoding	ns_per_op	3.8451	26615.0000	Avg: 25629.5294 Med: 25538.0000 Stdev: 384.3306	0.7860	2.5641

For a comprehensive view of all microbenchmark results for this PR's commit, please check out the Evergreen perf task for this patch.