[roll] Roll fuchsia [fidlc] Migrate from zxtest to gtest

This CL migrates all fidlc unit tests to use gtest instead of zxtest.
There are a few benefits to this:

* More engineeers are familiar with gtest, so it's more contributor
  friendly. zxtest is Fuchsia specific and has subtle differences.

* gtest uses operator<< after assertions to provide more information
  instead of printf-style arguments. This is more ergonomic, especially
  with std::string and std::string_view. For example:

      // zxtest
      FAIL("%s", str.c_str())
      FAIL("%.*s", static_cast<size_t>(sv.size()), sv.data());

      // gtest
      FAIL() << str;
      FAIL() << sv;

* gtest supports more expressive assertions with EXPECT_THAT /
  ASSERT_THAT and matchers like HasSubstr, Contains, etc.

* zxtest has incomplete support for parameterized tests. In a follow-up
  Icd9470addd3a503f536e29ac03e244b0739435df I'm using this feature, and
  found that with zxtest it compiled but silently ignored the tests.

* The build is a bit faster with gtest. Averaging over 5 builds
  (and appending comments to all test .cc files to defeat caching),
  fx build host_x64/fidlc-test was 17.2 +/- 1.2s with gtest, and
  24.8 +/- 2.9s with zxtest. Test runtime was identical, ~2.6s.

Original-Bug: 74490
Test: fx test fidlc-test
Original-Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/950761
Original-Revision: 229e5acff2cb91b7b77c283494f4bf8b7c21b55b
GitOrigin-RevId: 5206357d5040e22305eeffc3f5fc12574d970916
Change-Id: I59834df33f07a6bf265edf8e3ce49fb423a89019