renovate.json: adjust managers

We can apparently use the pep621 manager to manage uv dependencies
now. And we need to disable the pip_requirements manager so the bot
doesn't try to update our requirements.txt file (which is exported
from uv).

renovate.json

@@ -3,7 +3,7 @@
   "extends": [
     "config:recommended"
   ],
-  "pep621": {
-    "enabled": false
+  "pip_requirements": {
+      "enabled": false
   }
 }

requirements.txt

@@ -327,9 +327,9 @@ python-dateutil==2.9.0.post0 \
 python-stdnum==1.20 \
     --hash=sha256:111008e10391d54fb2afad2a10df70d5cb0c6c0a7ec82fec6f022cb8712961d3 \
     --hash=sha256:ad2a2cf2eb025de408210235f36b4ae31252de3186240ccaa8126e117cb82690
-pytz==2025.1 \
-    --hash=sha256:89dd22dca55b46eac6eda23b2d72721bf1bdfef212645d81513ef5d03038de57 \
-    --hash=sha256:c2db42be2a2518b28e65f9207c4d05e6ff547d1efa4086469ef855e4ab70178e
+pytz==2024.2 \
+    --hash=sha256:2aa355083c50a0f93fa581709deac0c9ad65cca8a9e9beac660adcbd493c798a \
+    --hash=sha256:31c7c1817eb7fae7ca4b8c7ee50c72f93aa2dd863de768e1ef4245d426aa0725
 requests==2.32.3 \
     --hash=sha256:55365417734eb18255590a9ff9eb97e9e1da868d4ccd6402399eaf68af20a760 \
     --hash=sha256:70761cfe03c773ceb22aa2f671b4757976145175cdfca038c02654d061d6dcc6