Replace Linkup web search with Serper (#717) #6706

Job	Run time
build-and-check	3m 18s
test-integration-packages/internal	1m 16s
test-integration-packages/billing	1m 6s
test-integration-packages/agent-runtime	39s
test-sdk	55s
test-integration-cli	47s
test-packages/internal	50s
test-common	40s
test-web	1m 11s
test-packages/billing	52s
test-.agents	42s
test-packages/agent-runtime	46s
test-integration-sdk	1m 56s
test-integration-common	45s
test-cli	1m 2s
test-integration-web	54s
	17m 39s

Provide feedback