added ubi8 hx build workflow

Author: NewtonChutney

.github/workflows/rhel-build.yaml

@@ -0,0 +1,49 @@
+name: RHEL Build
+
+on:
+    push:
+        branches:
+            - rhel-ubi-build
+        tags:
+            - 'ubi*'
+    workflow_dispatch:
+        inputs:
+            commit_hash:
+                description: 'Commit hash to build'
+                required: false
+                default: 'HEAD'
+    # pull_request:
+    #     branches:
+    #         - rhel-ubi-build
+
+jobs:
+    build:
+        runs-on: ubuntu-latest
+
+        steps:
+        - name: Checkout code
+          uses: actions/checkout@v2
+          with:
+            ref: ${{ github.event.inputs.commit_hash }}
+
+        - name: Set up Docker Buildx
+          uses: docker/setup-buildx-action@v1
+        
+        - name: Cache rust build deps
+          uses: Swatinem/rust-cache@v2
+        
+        - name: Build with RHEL8 UBI image
+          run: |
+                docker run --rm -v $(pwd):/workspace -w /workspace registry.access.redhat.com/ubi8/ubi:latest /bin/bash -c "
+                    yum install -y gcc-c++ git rust cargo &&
+                    export HELIX_DEFAULT_RUNTIME=/tmp/helix/runtime &&
+                    export HELIX_DISABLE_AUTO_GRAMMAR_BUILD &&
+                    cargo build --profile opt --locked
+                    "
+        # cargo build --release --path helix-term --locked
+
+        - name: Backup artifact
+          uses: actions/upload-artifact@v4
+          with:
+            name: helix
+            path: target/opt/hx