chore(swift): update Package.swift with checksum for v1.2.6

Go module tag packages/go/v1.2.6

Go module tag packages/go/v1/v1.2.6

chore(swift): update Package.swift with checksum for v1.2.5

Go module tag packages/go/v1.2.5

Go module tag packages/go/v1/v1.2.5

chore(swift): update Package.swift with checksum for v1.2.3

Go module tag packages/go/v1.2.3