test: Pass proto_ver to do_test() functions that require it

[mattst88]

These test scripts all contain a finally: block that attempts to print proto_ver which does not exist:

print("proto_ver=%d" % (proto_ver))

This mistake appears to be a copy-and-paste error in commit b2a9daf ("02 broker subpub tests with v5 support") and went unnoticed because the code is only reached if the tests fail.

Fixes: b2a9daf1 ("02 broker subpub tests with v5 support") Closes: https://github.com/eclipse-mosquitto/mosquitto/issues/3123

[mattst88]

@ralight: could you please have a look at this trivial PR?

[mattst88]

@ralight: I went through the hassle of signing the CLA. Can you have a look now?

[ralight]

Thanks very much.