[heft-jest-plugin] Fix --test-path-pattern being ignored on Jest 30

[iclanton]

Summary

heft test --test-path-pattern <regex> was silently running every test in a project. The Heft Jest plugin was passing the regex to Jest under the field name testPathPattern (singular) on Config.Argv.

Root cause

In Jest 30, the Config.Argv property was renamed from testPathPattern (singular) to testPathPatterns (plural). jest-config now treats the old name as deprecated and ignores it, which causes Jest to run with no path filter at all.

See jest-config v30:

testPathPattern: () => formatDeprecation(
  'Option *testPathPattern* was replaced by *--testPathPatterns*. '
  + '*--testPathPatterns* is only available as a command-line option.'
)

Fix

Write the argv as testPathPatterns (plural). The user-facing CLI parameter and the IJestPluginOptions.testPathPattern option are unchanged.

Repro

In libraries/rush-lib:

heft test --test-path-pattern ChangeFile.test

Before the fix this ran the entire suite. After the fix it correctly runs only ChangeFile.test.js.