Snapshot language syntax highlighting broken by < character.

[alumni]

Environment

1. vscode-jest version: [5.2.3]
2. node -v: [irrelevant]
3. npm -v or yarn --version: [irrelevant]
4. npm ls jest or npm ls react-scripts (if you haven’t ejected): [irrelevant]
5. your vscode-jest settings if customized:
   • jest.jestCommandLine? [irrelevant]
   • jest.autoRun? [irrelevant]
   • anything else that you think might be relevant? [irrelevant]
6. Operating system: [irrelevant]

Prerequisite

• are you able to run jest test from the command line? [X]
• how do you run your tests from the command line? (for example: npm run test or node_modules/.bin/jest) [irrelevant]

Steps to Reproduce

expect(value).toMatchSnapshot({ property: expect.any(String) });

will generate:

{
  "property": Any<String>,
}

This is not highlighted correctly.

Relevant Debug Info

[irrelevant]

Expected Behavior

Syntax highlighting works for snapshot file containing <.

Actual Behavior

Syntax highlighting doesn't work for snapshot file containing <.

Seems this is an issue in the TextMate grammar that was copied by most extensions. Similar issue: tlent/jest-snapshot-language-support#2

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