Try avoid duplicated github actions in PRs

.github/workflows/node.yml

@@ -2,6 +2,8 @@ name: Node
 
 on:
   push:
+    branches:
+      - master
     paths-ignore:
       - bindings/python/**
   pull_request:

.github/workflows/python.yml

@@ -2,6 +2,8 @@ name: Python
 
 on:
   push:
+    branches:
+      - master
     paths-ignore:
       - bindings/node/**
   pull_request:

.github/workflows/rust.yml

@@ -1,6 +1,10 @@
 name: Rust
 
-on: [push, pull_request]
+on:
+  push:
+    branches:
+      - master
+  pull_request:
 
 jobs:
   build: