Change isAccepted method to check for OA3 file to reduce error output

[springframeworkguru]

OpenAPI files start with openapi: "3.0.2, check for this and suppress error logging if yaml file is not an OpenAPI file.

This will reduce log output of errors in projects with OA3 yaml files, and non-OA3 yaml files.

Should not generate error log messages if OA3 contracts and SCC contracts are found in the same directory path.