feature: @oneOf input object support #1595

Job	Run time
Cocoapods Integration Tests - macOS	11s
changes	4s
Codegen Test Configurations - macOS	3m 57s
Run swift build for SPM packages (apollo-ios)	44s
Run swift build for SPM packages (apollo-ios-codegen)	31s
Run swift build for SPM packages (apollo-ios-pagination)	43s
Verify Frontend Bundle Latest - macOS	12s
Run Tuist Generation	3m 37s
Verify CLI Binary Archive - macOS	6s
Apollo Unit Tests - macOS	2m 24s
Codegen CLI Unit Tests - macOS	1m 28s
Codegen Lib Unit Tests - macOS	2m 33s
ApolloPagination Unit Tests - macOS	1m 24s
	17m 54s

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