Install CMake in the `gcc:13` container.

Change-Id: I097a186c45fbed2a2300a5675466bd253d4883ac
Reviewed-on: https://code-review.googlesource.com/c/re2/+/61313
Reviewed-by: Paul Wankadia <junyer@google.com>
Reviewed-by: Perry Lorier <perryl@google.com>