chore: release 3.1.0 (#500)

* chore: release 3.1.0

Release-As: 3.1.0

* fix: Restore prerelease config

Author: zguesmi

release-please-config.json

@@ -33,7 +33,10 @@
     "packages/subgraph": {
       "release-type": "node",
       "changelog-path": "CHANGELOG.md",
-      "include-v-in-tag": true
+      "include-v-in-tag": true,
+      "prerelease": true,
+      "prerelease-type": "beta",
+      "versioning": "prerelease"
     },
     "packages/smart-contract": {
       "release-type": "node",