Add FilterBuilder for Metadata Filter Construction #139

Job	Run time
linting / lint	9s
unit-tests / Type checking (3.9, false)	24s
unit-tests / Type checking (3.9, true)	25s
unit-tests / Unit (3.9)	24s
unit-tests / Unit grpc (3.9)	22s
create-project	0s
cleanup-project / cleanup-project	36s
integration-tests	0s
	2m 20s

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