Prep for March 5 0.13.1 support on Sepolia (#1158)

* Prep for 0.13.1 support on Goerli

* Add 0.13.1 on Sepolia to footer, current version support.

* Apply suggestions from code review

* Update playbook.yml

* Update playbook.yml

playbook.yml

@@ -40,7 +40,7 @@ asciidoc:
     # These attributes define the version footer, located in the starknet-docs-antora-ui project,
     # In /src/partials/, in the files footer-content.hbs and starknet_version.hbs.
     starknet_mainnet_version: 'Mainnet: 0.13.0'
-    starknet_testnet_version: 'Sepolia testnet: 0.13.0 | Goerli testnet: 0.13.0'
+    starknet_testnet_version: 'Sepolia testnet: 0.13.1 | Goerli testnet: 0.13.0'
     page-starknet_version: '{starknet_mainnet_version} | {starknet_testnet_version}'