Add suppressor for IDE0058 on StringBuilder and Directory (#762) #1330

Job	Run time
compute_package_version	5s
build_and_test (ubuntu-latest, Release, roslyn3.8)	2m 59s
build_and_test (ubuntu-latest, Release, roslyn4.2)	3m 12s
build_and_test (ubuntu-latest, Release, roslyn4.4)	2m 56s
build_and_test (ubuntu-latest, Release, roslyn4.6)	2m 58s
build_and_test (ubuntu-latest, Release, roslyn4.8)	2m 55s
build_and_test (ubuntu-latest, Release, default)	2m 58s
build_and_test (windows-latest, Release, roslyn3.8)	6m 30s
build_and_test (windows-latest, Release, roslyn4.2)	7m 19s
build_and_test (windows-latest, Release, roslyn4.4)	7m 9s
build_and_test (windows-latest, Release, roslyn4.6)	7m 8s
build_and_test (windows-latest, Release, roslyn4.8)	6m 51s
build_and_test (windows-latest, Release, default)	7m 2s
create_nuget	2m 4s
validate_nuget	44s
deploy	28s
create_release	13s
	1h 3m 31s

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