refactor(fs): prefer our fs and fs to fs-extra (pt2: test files)

[Hweinstock]

Problem

Follow up from #5689, focusing on the test files.

Solution

Mostly direct translation, one implementation change from writeJson to Json.stringify then writeFile in packages/core/src/test/awsService/cdk/detectCdkProjects.test.ts line 120

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License: I confirm that my contribution is made under the terms of the Apache 2.0 license.

[Hweinstock]

/runIntegrationTests

[Hweinstock]

/runIntegrationTests

[justinmk3]

this failure on the "minimum" unit test job might be relevant to this PR?

  3 failing
  1) CodeDownloader
       "after each" hook for "should return an error if the response body is not Buffer":
     EntryIsADirectory (FileSystemError): Error: EISDIR: illegal operation on a directory, unlink '/tmp/aws-toolkit-vscode/vsctk4b58ed57'
      at Function._handleError (/tmp/.vscode-test/vscode-linux-x64-1.68.0/resources/app/out/vs/workbench/api/node/extensionHostProcess.js:83:121929)
      at Object.delete (/tmp/.vscode-test/vscode-linux-x64-1.68.0/resources/app/out/vs/workbench/api/node/extensionHostProcess.js:83:121007)
      at runMicrotasks (<anonymous>)
      at processTicksAndRejections (node:internal/process/task_queues:96:5)
      at async Context.<anonymous> (/codebuild/output/src373008039/src/github.com/aws/aws-toolkit-vscode/packages/core/src/test/eventSchemas/commands/downloadSchemaItemCode.test.ts:52:9)

  2) CodeGenerator
       "after each" hook for "should return the current status of code generation":
     EntryIsADirectory (FileSystemError): Error: EISDIR: illegal operation on a directory, unlink '/tmp/aws-toolkit-vscode/vsctkddbc90b6'
      at Function._handleError (/tmp/.vscode-test/vscode-linux-x64-1.68.0/resources/app/out/vs/workbench/api/node/extensionHostProcess.js:83:121929)
      at Object.delete (/tmp/.vscode-test/vscode-linux-x64-1.68.0/resources/app/out/vs/workbench/api/node/extensionHostProcess.js:83:121007)
      at runMicrotasks (<anonymous>)
      at processTicksAndRejections (node:internal/process/task_queues:96:5)
      at async Context.<anonymous> (/codebuild/output/src373008039/src/github.com/aws/aws-toolkit-vscode/packages/core/src/test/eventSchemas/commands/downloadSchemaItemCode.test.ts:132:9)

  3) CodeGeneratorStatusPoller
       "after each" hook for "should return the current status of code generation":
     EntryIsADirectory (FileSystemError): Error: EISDIR: illegal operation on a directory, unlink '/tmp/aws-toolkit-vscode/vsctkc02d59ff'
      at Function._handleError (/tmp/.vscode-test/vscode-linux-x64-1.68.0/resources/app/out/vs/workbench/api/node/extensionHostProcess.js:83:121929)
      at Object.delete (/tmp/.vscode-test/vscode-linux-x64-1.68.0/resources/app/out/vs/workbench/api/node/extensionHostProcess.js:83:121007)
      at runMicrotasks (<anonymous>)
      at processTicksAndRejections (node:internal/process/task_queues:96:5)
      at async Context.<anonymous> (/codebuild/output/src373008039/src/github.com/aws/aws-toolkit-vscode/packages/core/src/test/eventSchemas/commands/downloadSchemaItemCode.test.ts:205:9)

[Hweinstock]

/runIntegrationTests

[Hweinstock]

/runIntegrationTests

[Hweinstock]

Yep, looks fixed now. The last one is the one fixed here: #5725

[justinmk3]

does assert.doesNotReject work?