fix: LoaderContext type

[SyMind]

What kind of change does this PR introduce?

Type wrong.

Did you add tests for your changes?

The resourcePath, resourceQuery, and resourceFragment properties within LoaderRunnerLoaderContext may not be defined if a loader is invoked without an associated resource.

For evidence of this behavior, refer to the test case located in test/cases/loaders/query/index.js. The test titled "should pass query to loader without resource" confirms this scenario.

However, this behavior could lead to type errors for loaders written in TypeScript. To address this, the loader-runner can be updated to assign an empty string as a default value for these properties.

Which plan do you think is better?

Does this PR introduce a breaking change?

What needs to be documented once your changes are merged?

[linux-foundation-easycla]

• ✅login: SyMind / (e29ce63)

The committers listed above are authorized under a signed CLA.

[webpack-bot]

For maintainers only:

• This needs to be documented (issue in webpack/webpack.js.org will be filed when merged)
• This needs to be backported to webpack 4 (issue will be created when merged)