ci: migrate all GitHub workflows to use self-hosted runner (#18)

Author: shtse8

.github/workflows/ci.yml

@@ -8,7 +8,7 @@ on:
 
 jobs:
   ci:
-    runs-on: ubuntu-latest
+    runs-on: [self-hosted, linux, x64]
     steps:
       - uses: actions/checkout@v4
 

.github/workflows/release.yml

@@ -6,7 +6,7 @@ on:
 
 jobs:
   release:
-    runs-on: ubuntu-latest
+    runs-on: [self-hosted, linux, x64]
     permissions:
       contents: write
       pull-requests: write