fix(js): do not generate explicit vitest task config for a js library unless adding plugin is disabled (#29606)

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## Current Behavior
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Generating a js library with any bundler other than `vite` and with the
`vitest` test runner results in an explicit `test` task in the project
configuration.

## Expected Behavior
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Generating a js library with any bundler other than `vite` and with the
`vitest` test runner should not generate an explicit `test` task in the
project configuration. The `test` task should be inferred.

## Related Issue(s)
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merged. -->

Fixes #

packages/js/src/generators/library/library.ts

@@ -172,6 +172,7 @@ export async function libraryGeneratorInternal(
       testEnvironment: options.testEnvironment,
       runtimeTsconfigFileName: 'tsconfig.lib.json',
       compiler: options.compiler === 'swc' ? 'swc' : 'babel',
+      addPlugin: options.addPlugin,
     });
     tasks.push(vitestTask);
     createOrEditViteConfig(