build-script-impl: propagate --verbose-build to nested CMake builds

[edymtt]

The main goal of this change is to ensure that the new build of the stdlib matches the same level of verbosity of the compiler build that spawned it.

For now I'm not matching this behaviour to the regular CMake build products (which would be needed if want to target external projects configured in LLVM).

Addresses rdar://144256800

[edymtt]

@swift-ci please python lint

[etcwilde]

@swift-ci please smoke test

[edymtt]

This behaves as expected -- from the macOS smoke test log

...
[1882/2276][ 82%][1053.355s] cd /Users/ec2-user/jenkins/workspace/swift-PR-macos-smoke-test/branch-main/build/buildbot_incremental/swift-macosx-x86_64/swift-stdlib-macosx-arm64-core-prefix/src/swift-stdlib-macosx-arm64-core-build && /Applications/CMake.app/Contents/bin/cmake --build . && /Applications/CMake.app/Contents/bin/cmake -E touch /Users/ec2-user/jenkins/workspace/swift-PR-macos-smoke-test/branch-main/build/buildbot_incremental/swift-macosx-x86_64/swift-stdlib-macosx-arm64-core-prefix/src/swift-stdlib-macosx-arm64-core-stamp/swift-stdlib-macosx-arm64-core-build
Change Dir: '/Users/ec2-user/jenkins/workspace/swift-PR-macos-smoke-test/branch-main/build/buildbot_incremental/swift-macosx-x86_64/swift-stdlib-macosx-arm64-core-prefix/src/swift-stdlib-macosx-arm64-core-build'

Run Build Command(s): /Users/ec2-user/jenkins/workspace/swift-PR-macos-smoke-test/branch-main/build/buildbot_incremental/ninja-build/ninja -v
[1/109][  0%][1.078s] /Applications/Xcode-beta.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang++ --target=arm64-apple-macosx13.0 -DSWIFT_ENABLE_REFLECTION -DSWIFT_HAVE_CRASHREPORTERCLIENT -DSWIFT_INLINE_NAMESPACE=__runtime -DSWIFT_LIBRARY_EVOLUTION -DSWIFT_OBJC_INTEROP -DSWIFT_RUNTIME_CLOBBER_FREED_OBJECTS=0 -DSWIFT_RUNTIME_ENABLE_LEAK_CHECKER=0 -DSWIFT_RUNTIME_OS_VERSIONING -DSWIFT_STDLIB_ENABLE_UNICODE_DATA -DSWIFT_STDLIB_HAS_ASL -DSWIFT_STDLIB_HAS_DARWIN_LIBMALLOC -DSWIFT_STDLIB_HAS_STDIN -DSWIFT_STDLIB_HAS_TYPE_PRINTING -DSWIFT_SUPPORT_OLD_MANGLING -DSWIFT_THREADING_DARWIN -DswiftCore_EXPORTS -I/Users/ec2-user/jenkins/workspace/swift-PR-macos-smoke-test/branch-main/swift/Runtimes/Core/include -I/Users/ec2-user/jenkins/workspace/swift-PR-macos-smoke-test/branch-main/swift/Runtimes/Core/../../include -I/Users/ec2-user/jenkins/workspace/swift-PR-macos-smoke-test/branch-main/build/buildbot_incremental/swift-macosx-x86_64/swift-stdlib-macosx-arm64-core-prefix/src/swift-stdlib-macosx-arm64-core-build/include -I/Users/ec2-user/jenkins/workspace/swift-PR-macos-smoke-test/branch-main/swift/Runtimes/Core/SwiftShims/swift/shims/../.. -O3 -DNDEBUG -std=c++17 -isysroot /Applications/Xcode-beta.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX14.2.sdk -mmacosx-version-min=13.0 -fvisibility=hidden -fvisibility-inlines-hidden -mcx16 -fno-rtti -fno-exceptions -funwind-tables -MD -MT Demangling/CMakeFiles/swiftDemangling.dir/Users/ec2-user/jenkins/workspace/swift-PR-macos-smoke-test/branch-main/swift/lib/Demangling/Errors.cpp.o -MF Demangling/CMakeFiles/swiftDemangling.dir/Users/ec2-user/jenkins/workspace/swift-PR-macos-smoke-test/branch-main/swift/lib/Demangling/Errors.cpp.o.d -o Demangling/CMakeFiles/swiftDemangling.dir/Users/ec2-user/jenkins/workspace/swift-PR-macos-smoke-test/branch-main/swift/lib/Demangling/Errors.cpp.o -c /Users/ec2-user/jenkins/workspace/swift-PR-macos-smoke-test/branch-main/swift/lib/Demangling/Errors.cpp
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