feat(sca): add extra_headers to sca diff scan

Author: xblanchot-gg

pygitguardian/client.py

@@ -677,6 +677,7 @@ def scan_diff(
         reference: bytes,
         current: bytes,
         scan_parameters: SCAScanParameters,
+        extra_headers: Optional[Dict[str, str]] = None,
     ) -> Union[Detail, SCAScanDiffOutput]:
         result: Union[Detail, SCAScanDiffOutput]
         try:
@@ -686,6 +687,7 @@ def scan_diff(
                 data={
                     "scan_parameters": SCAScanParameters.SCHEMA.dumps(scan_parameters)
                 },
+                extra_headers=extra_headers,
             )
         except requests.exceptions.ReadTimeout:
             result = Detail("The request timed out.")