Update and Fix check_ssl_cert

[srvrguy]

The check_ssl_cert command that is included in the image is broken in a few ways:

• Missing the "file" command, which it relies on
• Always errors out on default behavior because the OCSP check doesn't work

This PR makes a few small changes that get the command working again:

• Updates to the most recent version of check_ssl_cert, which brings three years of updates and fixes
• Installs the file and bc packages required by the default script behavior

[cla-bot[bot]]

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Contributors that have not signed yet: @srvrguy

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[srvrguy]

The company where I work has signed the CCLA. How can I clear the error status from this?

[bobapple]

@cla-bot check

[srvrguy]

Thank you for the feedback. I've updated the PR to include the changes.