mod: bump google.golang.org/grpc from 1.76.0 to 1.77.0 #18416

Job	Run time
aux	4m 42s
dashboard	2m 3s
build	5m 32s
race_dashboard	3m 47s
race	9m 14s
gvisor	4m 9s
arch (presubmit_arch_freebsd)	6m 28s
arch (presubmit_arch_linux)	10m 45s
arch (presubmit_arch_netbsd)	3m 50s
arch (presubmit_arch_openbsd)	3m 44s
old	7m 12s
arch (presubmit_arch_windows)	3m 40s
arch (presubmit_arch_darwin)	3m 46s
arch (presubmit_arch_executor)	3m 14s
	1h 12m 6s

Provide feedback