Automatic merge from submit-queue

Use pause image depending on the server's platform when testing

Removed all pause image constant strings, now the pause image is chosen by arch. Part of the effort of making e2e arch-agnostic.

The pause image name and version is also now only in two places, and it's documented to bump both
Also removed "amd64" constants in the code. Such constants should be replaced by `runtime.GOARCH` or by looking up the server platform

Fixes: #22876 and #15140
Makes it easier for: #25730
Related: #17981

This is for `v1.3`
@ixdy @thockin @vishh @kubernetes/sig-testing @andyzheng0831 @pensu