Update branch name in CI file

Author: knutwalker

.github/workflows/checks.yml

@@ -3,10 +3,10 @@ name: checks
 on:
   push:
     branches:
-      - "0.8"
+      - v0.8
   pull_request:
     branches:
-      - "0.8"
+      - v0.8
   release:
     types: [published]
   merge_group:

.github/workflows/create-release-pr.yml

@@ -75,4 +75,4 @@ jobs:
           version: ${{ inputs.version }}
           crate-name: ${{ inputs.crate || 'neo4rs' }}
           check-semver: true
-          base-branch: '0.8'
+          base-branch: 'v0.8'