v2.5.0

Features

• Opentelemetry integration (#1078) (76db007), closes #1066 #1070

Bug Fixes

• make request batching work again (#1087) (80e0ee3)
• properly handle non-emulator alternate endpoints for pub/sub (#1060) (195ebf6)
• deps: update opentelemetry monorepo to ^0.10.0 (#1090) (78a45ff)
• update minimum gax version to 2.7.0 to fix recent protobuf errors (#1085) (904348c)