Fix Python 3 compatibility in API enrichment test servers

- Replace deprecated headers.getheader() with headers.get()
- Fix base64.b64encode() to work with bytes in Python 3
- Replace base64.decodestring() with base64.b64decode()

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: joaolcorreia

integration-tests/common-fs2/api-enrichment-test.py

@@ -38,7 +38,7 @@ def do_POST(self):
             self.write_body(response)
         else:
             self.do_AUTHHEAD()
-            self.write_body(self.headers.getheader('Authorization'))
+            self.write_body(self.headers.get('Authorization') or '')
             self.write_body('not authenticated')
 
     def do_GET(self):

integration-tests/common/api-enrichment-test.py

@@ -20,7 +20,8 @@ def do_POST(self):
         ''' Present frontpage with user authentication. '''
         self.post_request_counter += 1
         self.protocol_version='HTTP/1.1'
-        auth = self.headers.getheader('Authorization')
+        auth = self.headers.get('Authorization')
+        expected_auth = 'Basic ' + base64.b64encode(b'snowplower:supersecret').decode('utf-8')
         if self.path.startswith("/guest"):
             self.send_response(200)
             response = self.generate_response("POST")
@@ -30,15 +31,15 @@ def do_POST(self):
         elif auth is None:
             self.do_AUTHHEAD()
             self.write_body('no auth header received')
-        elif auth == 'Basic ' + base64.b64encode('snowplower:supersecret'):
+        elif auth == expected_auth:
             response = self.generate_response("POST", auth)
             self.send_response(200)
             self.send_header('Content-length', len(response))
             self.end_headers()
             self.write_body(response)
         else:
             self.do_AUTHHEAD()
-            self.write_body(self.headers.getheader('Authorization'))
+            self.write_body(self.headers.get('Authorization') or '')
             self.write_body('not authenticated')
 
     def do_GET(self):
@@ -57,7 +58,7 @@ def do_GET(self):
 
     def generate_response(self, method, auth=None):
         if auth is not None:
-            userpass = base64.decodestring(auth[6:])
+            userpass = base64.b64decode(auth[6:]).decode('utf-8')
             response = {
                 "rootNull": None,
                 "data": {