verify.sh: Don't exit on error in _run_and_verify_*() funcs. (#7359)
verify.sh: Don't exit on error in _run_and_verify_*() funcs. (#7359)

* verify.sh: Don't exit on error in _run_and_verify_*() funcs.

Most tests include "set -e", which causes the script to exit if a
statement returns a non-true return value.  In some cases, the command
may exit with a non-true return value, but we want to retry the command
later.  We want to temporarily disable that "errexit" behavior.

* verify.sh: Clarify __verify_with_retry() comment and variable name.
istio/istio.io,istio/istio.io,istio/istio.io,istio/istio.io,istio/istio.io,istio/istio.io,istio/istio.io