Only validate non-empty queries that do not match all changes

Empty and * queries will just make the reviewer filter apply
in later processing. So they are always valid.

This change is a latency improvement since trying to construct a
query with `*` on servers that have account visibility checking will
cause Gerrit to lookup many accounts (through ChangeQueryBuilder ->
default -> parseAccount -> AccountResolver -> check).

Google-Bug: b/267202984
Change-Id: If9f5e879b05044e23b527d65838da6900a378956
1 file changed