Fix github workflow branches

Author: fontivan

.github/workflows/rust.yml

@@ -12,7 +12,7 @@ name: Rust
 on:  # yamllint disable-line rule:truthy
   pull_request:
     branches:
-      - main
+      - release-4.15
   push:
     branches:
-      - main
+      - release-4.15

.github/workflows/yamllint.yml

@@ -12,7 +12,7 @@ name: Yamllint
 on:  # yamllint disable-line rule:truthy
   pull_request:
     branches:
-      - main
+      - release-4.15
   push:
     branches:
-      - main
+      - release-4.15