* Update the private key regex validation
Private keys provided by the Let's Encrypt certificate authority as part
of their certificate bundle fail the import/upload certificate private
key validation. The validation is looking for a specific character
sequence at the begin of the certificate. In order to support valid
Let's Encrypt private keys, the regex has been updated to check for both
the existing sequence and the Let's Encrypt character sequence.
Example Let's Encrypt private key:
-----BEGIN PRIVATE KEY-----
MIIEvQIBADANBgkqhkiG9w0BAQEFAASCBKcwggSjAgEAAoIBAQCvsiwV8A5+r0tQ
QzUAJO0DfoEb9tMWvoFi0DLs9tx88IwMqItPPl9+RNzQnv9qqZR1h4W97sxP8aWY
...
AeS667IJO/2DMKaGiEldaVZtgqdUhCL8Rm4XUFVb1GjLa03E4VRU6W7eQ4hgT2a7
cHDAR8MiovNyfT0fm8Xz3ac=
-----END PRIVATE KEY-----
* Add private key regex for footer
Update the import/upload private key validation regex to verify both the
header and footer are matching.
9065aa3750