add doc and script to check certificates

docs/grep-certificates.md

 # How to check when the certificates stored on sgxwallet were created
+- Download file `scripts/grep_certificates.py` from the sgxwallet repository and put it in sgxwallet repository directory on your machine.
 - Go to sgxwallet repository directory.
-- Run `python3 scripts/grep_certificates.py PATH_TO_SGXWALLET_DB_FOLDER`. PATH_TO_SGXWALLET_DB_FOLDER - full path to the `sgx_data` directory where sgxwallet db is stored. For example, `root/sgxwallet/run_sgx/sgx_data`
+- Run `python3 grep_certificates.py PATH_TO_SGXWALLET_DB_FOLDER`. PATH_TO_SGXWALLET_DB_FOLDER - path (either absolute or relative) to the `sgx_data` directory where sgxwallet db is stored. For example, `/root/sgxwallet/run_sgx/sgx_data` or `run_sgx/sgx_data`
 - The script will output the dates when every certificate was created.
 - Go to skale-node and run `cat .skale/node_data/sgx_certs/sgx.crt | grep "Not Before"`.
 - Ensure that the output of the last command exists in the list from step 3 and it is the latest certificate there! 
\ No newline at end of file

scripts/grep_certificates.py

@@ -31,6 +31,7 @@ def main():
             for line in file_one:
                 if re.search(pattern, line):
                     print(line)
+                    break
 
 
 if __name__ == '__main__':