Fix integration test nonce handling to use URL-safe base64 consistently

The integration test generators were incorrectly converting from URL-safe
base64 to standard base64, which causes nonce freshness validation to fail
when the verification API now consistently uses URL-safe base64 encoding.

This removes the erroneous conversions for both PSA and CCA schemes,
ensuring consistent URL-safe base64 usage throughout the system.

Signed-off-by: Kallal Mukherjee <[email protected]>

Author: kallal79

integration-tests/utils/generators.py

@@ -128,20 +128,18 @@ 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('_', '/')
+        # Use nonce directly as URL-safe base64 to match verification API
         update_json(
                 f'data/claims/{scheme}.{evidence}.json',
-                {f'{scheme}-nonce': translated_nonce},
+                {f'{scheme}-nonce': nonce},
                 claims_file,
                 )
     elif scheme == 'cca' and nonce:
         claims_file = f'{GENDIR}/claims/{scheme}.{evidence}.json'
-        # convert nonce from base64url to base64
-        translated_nonce = nonce.replace('-', '+').replace('_', '/')
+        # Use nonce directly as URL-safe base64 to match verification API
         update_json(
                 f'data/claims/{scheme}.{evidence}.json',
-                {'cca-realm-delegated-token': {f'cca-realm-challenge': translated_nonce}},
+                {'cca-realm-delegated-token': {f'cca-realm-challenge': nonce}},
                 claims_file,
                 )
     else: