ci: minimal CI testing setup

Add static and shared build and runtime testing.

.github/workflows/test.yml

@@ -0,0 +1,38 @@
+name: USDT CI
+
+on:
+  push:
+    branches: [ "main" ]
+  pull_request:
+    branches: [ "main" ]
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v4
+      with:
+        ref: main
+
+    - name: look around
+      run: pwd; ls -la; ls -la tests
+
+    - name: wtf
+      run: make -C tests list
+
+    - name: wtf 2
+      run: make -C tests test-arg_nums
+
+    - name: Build (static)
+      run: make SHARED=0 -C tests -j$(nproc) build
+
+    - name: Build (shared)
+      run: make SHARED=1 -C tests -j$(nproc) build
+
+    - name: Test (static)
+      run: make SHARED=0 -C tests test
+
+    - name: Test (shared)
+      run: make SHARED=1 -C tests test