Fix integration tests: Convert URL-safe base64 nonces to standard base64 for PSA tokens

- PSA evidence token generation (evcli psa create) expects standard base64 nonces
- Server now returns URL-safe base64 nonces in challenge-response sessions
- Added conversion from URL-safe to standard base64 for PSA claims generation
- Matches existing conversion logic already used for CCA tokens
- Resolves 'illegal base64 data' errors in integration tests

Author: 7908837174

integration-tests/utils/generators.py

@@ -128,9 +128,11 @@ def generate_evidence(scheme, evidence, nonce, signing, outname):
 
     if scheme == 'psa' and nonce:
         claims_file = f'{GENDIR}/claims/{scheme}.{evidence}.json'
+        # convert nonce from base64url to base64
+        translated_nonce = nonce.replace('-', '+').replace('_', '/')
         update_json(
                 f'data/claims/{scheme}.{evidence}.json',
-                {f'{scheme}-nonce': nonce},
+                {f'{scheme}-nonce': translated_nonce},
                 claims_file,
                 )
     elif scheme == 'cca' and nonce: