Remove pull_request event from build_and_minimal_test.yaml since push alone seems sufficient, and github runs duplicate jobs for the same PR if both events are present.
Remove pull_request event from build_and_minimal_test.yaml since push alone seems sufficient, and github runs duplicate jobs for the same PR if both events are present.

PiperOrigin-RevId: 368222742

google/fedjax,google/fedjax