Remove standalone linux build action

.github/workflows/linux_build.yml

@@ -1,29 +0,0 @@
-name: Build for Linux
-
-on:
-  workflow_dispatch:
-    inputs:
-      ref:
-        description: 'Ref to build (branch, tag or SHA)'
-        required: false
-        default: 'main'
-
-jobs:
-  build:
-    name: Build SwiftFormat for Linux
-    runs-on: ubuntu-20.04
-    steps:
-      - uses: actions/checkout@v4
-        with:
-          ref: ${{ github.event.inputs.ref }}
-      - name: Build it
-        run: |
-          swift build --configuration release --static-swift-stdlib --enable-dead-strip
-          SWIFTFORMAT_BIN_PATH=`swift build --configuration release --show-bin-path`
-          mv $SWIFTFORMAT_BIN_PATH/swiftformat "${HOME}/swiftformat_linux"
-      - name: 'Upload Artifact'
-        uses: actions/upload-artifact@v4
-        with:
-          name: swiftformat_linux
-          path: ~/swiftformat_linux
-          retention-days: 5