refactor: use t.TempDir() instead of os.MkdirTemp

[yuhangcangqian]

Description

TempDir returns a temporary directory for the test to use.The directory is automatically removed when the test and
all its subtests complete. More info https://pkg.go.dev/testing#B.TempDir

Type of change

Please delete options that are not relevant.

• [] Bug fix (non-breaking change which fixes an issue)
• [] New feature (non-breaking change which adds functionality)
• Code refactor or improvement
• [] Breaking change (fix or feature that would cause a new or changed behavior of existing functionality)
• [] This change requires a documentation update

How Has This Been Tested?

Please describe the tests that you ran to verify your changes. Provide instructions so we can reproduce. Please also list any relevant details for your test configuration

• make test
• [] fullsync
• [] Other test (please specify)

Test Configuration:

• Firmware version:
• Hardware:
• Toolchain:
• SDK:

Checklist:

• [] My code follows the style guidelines of this project
• [] I have performed a self-review of my code
• [] I have commented my code, particularly in hard-to-understand areas
• [] I have made corresponding changes to the documentation
• [] My changes generate no new warnings
• [] I have added tests that prove my fix is effective or that my feature works
• [] New and existing unit tests pass locally with my changes
• [] Any dependent changes have been merged and published in downstream modules

[CLAassistant]

All committers have signed the CLA.

[Copilot]

PR Overview

This pull request refactors the test files to use t.TempDir() instead of os.MkdirTemp(), thereby simplifying temporary directory creation and cleanup in tests.

• Replaced os.MkdirTemp with t.TempDir() in db_pebble_test.go for TestPebbleDB, TestPebbleDB_Filter, and TestPebbleDB_Foreach.
• Removed custom cleanup calls using testutil.CleanupPath as t.TempDir() automatically cleans up.

Reviewed Changes

File	Description
db/db_pebble_test.go	Refactored temporary directory creation in tests
server/itx/server_test.go	Updated temporary directory creation for action store

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
50.0% Duplication on New Code

See analysis details on SonarQube Cloud