fix: modify regex to enforce key name of "version"

Currently, regex will match anything with "version" in the key name. When tracking more than one version scheme, such as "apiVersion", and if that additional scheme is the first occurrence the regex finds, the bump will be applied to that key:value. 

Change to regex removes the ? modifier for quotes which A) enforces proper JSON format and B) restricts key name for the bump target to "version" (still case insensitive).