CI validates WASM support

For now failure is allowed as no work was done, but this should confirm the crate can at least be compiled
to that target.

Author: Byron

.github/workflows/wasm.yml

@@ -0,0 +1,31 @@
+name: WASM
+
+on:
+  push:
+    branches: [ main ]
+    tags-ignore: [ '*' ]
+    paths:
+      - '.github/**'
+      - 'git-pack/**'
+      - '*.toml'
+  pull_request:
+    branches: [ main ]
+    paths:
+      - '.github/**'
+      - 'git-pack/**'
+      - '*.toml'
+
+jobs:
+  compile-to-wasm:
+    runs-on: ubuntu-latest
+    continue-on-error: true
+    steps:
+      - uses: actions/checkout@v3
+      - uses: actions-rs/toolchain@v1
+        with:
+          toolchain: stable
+          target: wasm32-unknown-unknown
+          override: true
+          profile: minimal
+      - uses: Swatinem/rust-cache@v2
+      - run: cargo check -p git-pack --target wasm32-unknown-unknown