Turn on objc-* clang-tidy checks

[jmagman]

Turn on checks:

• objc-assert-equals
• objc-avoid-nserror-init
• objc-dealloc-in-category
• objc-forbidden-subclassing
• objc-missing-hash
• objc-nsdate-formatter
• objc-property-declaration
• objc-super-self

Keep objc-nsinvocation-argument-lifetime check off since OCMock macros are generating failures:

❌ Failures for clang-tidy on /Volumes/Work/s/w/ir/cache/builder/src/flutter/shell/platform/darwin/macos/framework/Source/FlutterChannelKeyResponderTest.mm:
/Volumes/Work/s/w/ir/cache/builder/src/flutter/shell/platform/darwin/macos/framework/Source/FlutterChannelKeyResponderTest.mm:48:33: error: NSInvocation '-getArgument:atIndex:' should only pass pointers to objects with ownership __unsafe_unretained [objc-nsinvocation-argument-lifetime,-warnings-as-errors]
        [invocation getArgument:&message atIndex:2];
                                ^
../../third_party/ocmock/Source/OCMock/OCMStubRecorder.h:55:30: note: expanded from macro 'andDo'
#define andDo(aBlock) _andDo(aBlock)

https://logs.chromium.org/logs/flutter/buildbucket/cr-buildbucket/8796856828802754401/+/u/test:_lint_host_debug/stdout

Pre-launch Checklist

• I read the Contributor Guide and followed the process outlined there for submitting PRs.
• I read the Tree Hygiene wiki page, which explains my responsibilities.
• I read and followed the Flutter Style Guide and the C++, Objective-C, Java style guides.
• I listed at least one issue that this PR fixes in the description above.
• I added new tests to check the change I am making or feature I am adding, or Hixie said the PR is test-exempt. See testing the engine for instructions on writing and running engine tests.
• I updated/added relevant documentation (doc comments with ///).
• I signed the CLA.
• All existing and new tests are passing.

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[cbracken]