fix: install pip deps in CI with --break-system-packages

Python 3.12 (PEP 668) blocks bare pip installs into the system.
Move the install step into the CI script and drop the self-install
fallback from the Python script.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.gitlab-ci.yml

@@ -12,6 +12,7 @@ sync-elo:
   only:
     - schedules
   script:
+    - pip3 install --break-system-packages requests openpyxl -q
     - python3 scripts/sync-elo.py
     - git config user.email ci@gateway-gamers.net
     - 'git config user.name "GG CI Bot"'

scripts/sync-elo.py

@@ -10,13 +10,6 @@ import sys
 from datetime import datetime, timezone
 from io import BytesIO
 
-try:
-    import requests
-    import openpyxl
-except ImportError:
-    print("Installing dependencies…", flush=True)
-    import subprocess
-    subprocess.check_call([sys.executable, "-m", "pip", "install", "requests", "openpyxl", "-q"])
 import requests
 import openpyxl