doc: fix reference to googletest test fixture

PR-URL: #35813
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Jiawen Geng <technicalcute@gmail.com>

Author: tniessen

doc/guides/writing-tests.md

@@ -444,4 +444,4 @@ Nightly coverage reports for the Node.js master branch are available at
 [all maintained branches]: https://github.com/nodejs/lts
 [directory structure overview]: https://github.com/nodejs/node/blob/master/test/README.md#test-directories
 [node.green]: https://node.green/
-[test fixture]: https://github.com/google/googletest/blob/master/googletest/docs/Primer.md#test-fixtures-using-the-same-data-configuration-for-multiple-tests
+[test fixture]: https://github.com/google/googletest/blob/master/googletest/docs/primer.md#test-fixtures-using-the-same-data-configuration-for-multiple-tests-same-data-multiple-tests