[copybara-service]

Replace legacy @hide package.html files with package-info.java in
AndroidX Test.

Remove the three remaining {@hide} package.html files in
androidx.test in favor of @RestrictTo(Scope.LIBRARY)
package-info.java declarations:

• Delete espresso/internal/package.html and add package-info.java
  annotated with @RestrictTo(Scope.LIBRARY) for
  androidx.test.espresso.internal.inject. The parent directory
  espresso/internal/ has no source files or BUILD target (so a
  package-info.java there would not be compiled, and @RestrictTo
  does not inherit to subpackages), while the other two subpackages
  under espresso/internal/ (data and data.model) already have
  package-info.java files with @RestrictTo(Scope.LIBRARY).
• Delete duplicate package.html files in
  androidx.test.internal.runner.tracker and
  androidx.test.services.storage.internal, which already have
  package-info.java files annotated with @RestrictTo(Scope.LIBRARY).

Replacing {@hide} package.html files with @RestrictTo
package-info.java declarations:

• Unlocks passing --ignore-comments on non-doc Metalava runs,
  improving build performance and memory usage by skipping Javadoc/HTML
  comment extraction and tag parsing.
• Enables Metalava declarative <api-surfaces> XML configuration,
  which ignores @hide and @removed doc tags by design.
• Enforces package-level visibility in compilers, Android Lint, Dackka,
  and IDEs (which do not propagate HTML @hide tags across packages).