fix: ensure lint rule only applies to test folders

---
type: pre_commit_static_analysis_report
description: Results of running static analysis checks when committing changes.
report:
  - task: lint_filenames
    status: passed
  - task: lint_editorconfig
    status: passed
  - task: lint_markdown
    status: na
  - task: lint_package_json
    status: na
  - task: lint_repl_help
    status: na
  - task: lint_javascript_src
    status: passed
  - task: lint_javascript_cli
    status: na
  - task: lint_javascript_examples
    status: na
  - task: lint_javascript_tests
    status: na
  - task: lint_javascript_benchmarks
    status: na
  - task: lint_python
    status: na
  - task: lint_r
    status: na
  - task: lint_c_src
    status: na
  - task: lint_c_examples
    status: na
  - task: lint_c_benchmarks
    status: na
  - task: lint_c_tests_fixtures
    status: na
  - task: lint_shell
    status: na
  - task: lint_typescript_declarations
    status: na
  - task: lint_typescript_tests
    status: na
  - task: lint_license_headers
    status: passed
---

Author: kgryte

lib/node_modules/@stdlib/_tools/eslint/rules/first-unit-test/lib/main.js

@@ -76,7 +76,11 @@ function main( context ) {
 		hasMainExportTest = false;
 		tOkExists = false;
 		filename = context.getFilename();
-		if ( contains( filename, 'test.' ) && !contains( filename, 'fixtures' ) ) {
+		if (
+			contains( filename, '/test/' ) &&
+			contains( filename, 'test.' ) &&
+			!contains( filename, 'fixtures' )
+		) {
 			if ( endsWith( filename, 'cli.js' ) ) {
 				forCLI = true;
 			}