Build action is broken due to release checks

[markus-boesch]

Build action is broken at step Running WebRTC release checks, starting 2026-05-07 :

Traceback (most recent call last):
  File "/Users/runner/work/WebRTC/WebRTC/scripts/release.py", line 129, in <module>
    nextRelease = getNextRelease()
  File "/Users/runner/work/WebRTC/WebRTC/scripts/release.py", line 42, in getNextRelease
    latestReleaseDate = datetime.fromisoformat(releases[0]["published_at"].replace("Z", ""))
                                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
AttributeError: 'NoneType' object has no attribute 'replace'
Error: Process completed with exit code 1.

Most recent version of WebRTC currently is M148.

See here for details.