chore(gitattributes): Mark more __snapshots__ directories as generated (#70421)
Noticed these files while reviewing https://github.com/vercel/next.js/pull/70242
Mark them as generated so that github & graphite collapse them when reviewing code.
```
$ git ls-files | git check-attr -a --stdin | grep __snapshots__
```
```
.config/ast-grep/rule-tests/__snapshots__/no-context-snapshot.yml: linguist-generated: true
examples/with-jest-babel/__tests__/__snapshots__/snapshot.tsx.snap: linguist-generated: true
examples/with-jest/__tests__/__snapshots__/snapshot.tsx.snap: linguist-generated: true
examples/with-typescript-graphql/test/__snapshots__/index.test.tsx.snap: linguist-generated: true
test/development/acceptance-app/__snapshots__/ReactRefreshLogBox.test.ts.snap: linguist-generated: true
test/development/acceptance/__snapshots__/ReactRefreshLogBox.test.ts.snap: linguist-generated: true
test/development/acceptance/__snapshots__/ReactRefreshLogBoxMisc.test.ts.snap: linguist-generated: true
test/development/acceptance/__snapshots__/error-recovery.test.ts.snap: linguist-generated: true
test/development/basic/__snapshots__/next-rs-api.test.ts.snap: linguist-generated: true
test/production/eslint/test/__snapshots__/next-build-and-lint.test.ts.snap: linguist-generated: true
```