Cache pluginval builds, add missing lv2 extension packages

Signed-off-by: falkTX <falktx@falktx.com>

.github/workflows/build.yml

@@ -1041,6 +1041,21 @@ jobs:
       - uses: actions/checkout@v2
         with:
           submodules: recursive
+      - name: Set up cache
+        id: cache
+        uses: actions/cache@v2
+        with:
+          path: |
+            src/Rack/dep/bin
+            src/Rack/dep/include
+            src/Rack/dep/lib
+            src/Rack/dep/share
+            src/Rack/dep/jansson-2.12
+            src/Rack/dep/libarchive-3.4.3
+            src/Rack/dep/libsamplerate-0.1.9
+            src/Rack/dep/speexdsp-SpeexDSP-1.2rc3
+            src/Rack/dep/zstd-1.4.5
+          key: pluginval-v${{ env.CACHE_VERSION }}
       - name: Set up dependencies
         run: |
           # custom repos
@@ -1050,7 +1065,7 @@ jobs:
           # build-deps
           sudo apt-get install -yqq libdbus-1-dev libgl1-mesa-dev liblo-dev libx11-dev libxcursor-dev libxext-dev libxrandr-dev
           # runtime testing
-          sudo apt-get install -yqq carla-git lilv-utils lv2-dev lv2lint valgrind xvfb
+          sudo apt-get install -yqq carla-git lilv-utils lv2-dev lv2lint kxstudio-lv2-extensions mod-lv2-extensions valgrind xvfb
       - name: Set up ccache
         uses: hendrikmuhs/ccache-action@v1.2
         with: