Minor fixes to reduce errors in our environment

[matthope]

• Use "-m1" argument to grep to only get the first match If some parameters in the YAML file match the word "expiration" this can mess up the check.
• Check if yaml report exists before running grep against it. If the certificates and reports get out of sync (say, you deleted some reports) you'll get some "No such file or directory"

[cafuego]

Excellent, thank you :-)