Add the server RPC executor. #1159

Job	Run time
Build and Test on swiftlang/swift:nightly-jammy	4m 20s
Build and Test on swiftlang/swift:nightly-jammy	4m 20s
Performance Tests on swiftlang/swift:nightly-jammy	11m 46s
Performance Tests on swiftlang/swift:nightly-jammy	11m 46s
Build and Test on swift:5.9-jammy	3m 45s
Build and Test on swift:5.9-jammy	3m 45s
Performance Tests on swift:5.9-jammy	10m 27s
Performance Tests on swift:5.9-jammy	10m 27s
Build and Test on swift:5.8-focal	3m 18s
Build and Test on swift:5.8-focal	3m 18s
Performance Tests on swift:5.8-focal	9m 23s
Performance Tests on swift:5.8-focal	9m 23s
License Header and Formatting Checks	6m 41s
License Header and Formatting Checks	6m 41s
Build and Test on swift:5.7-focal	3m 12s
Build and Test on swift:5.7-focal	3m 12s
Integration Tests on swiftlang/swift:nightly-jammy	3m 25s
Integration Tests on swiftlang/swift:nightly-jammy	3m 25s
Performance Tests on swift:5.7-focal	9m 15s
Performance Tests on swift:5.7-focal	9m 15s
Integration Tests on swift:5.9-jammy	21m 51s
Integration Tests on swift:5.9-jammy	2m 45s
Integration Tests on swift:5.8-focal	2m 17s
Integration Tests on swift:5.8-focal	2m 17s
Integration Tests on swift:5.7-focal	2m 16s
Integration Tests on swift:5.7-focal	2m 16s
	2h 44m 46s

Provide feedback