Adds cppgc_headers to v8_internal_headers and fuzzer_support to
lib_wasm_fuzzer_common in BUILD.gn as well as v8_libbase and
v8_libplatform to cctest_headers in test/cctest/BUILD.gn.

Bug: v8:7730
Change-Id: I9759bb0993be779ddfc26668b9e08503ea53bd69
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2727501
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Auto-Submit: Dan Elphick <delphick@chromium.org>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#73122}