reverting nightly to fix docker image mismatch (#887)

.github/workflows/poetry-publish-nightly.yml

@@ -97,7 +97,7 @@ jobs:
         if: steps.cache.outputs.cache-hit != 'true'
       - name: Build package under skyplane-dev name
         run: |
-          export RELEASEDATE=$(date +%Y%m%d%H%M)
+          export RELEASEDATE=$(date +%Y%m%d)
           echo "gateway_version = 'nightly-$RELEASEDATE'" > skyplane/gateway_version.py
           sed -i 's/name = "skyplane"/name = "skyplane-nightly"/g' pyproject.toml
           sed -i "s/version = \"\([0-9]\+\.[0-9]\+\.[0-9]\+\)\(.*\)\"/version = \"\1.dev$RELEASEDATE\"/" pyproject.toml