CI: run cargo test, cargo check and cargo audit

also remove the installation of the arm target and `flip-link` as the
crate is no longer being built against an STM32.

Author: rursprung

.github/workflows/CI.yml

@@ -14,19 +14,23 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-      - name: Install target
-        run: rustup target add thumbv7em-none-eabihf
-      - name: Install flip-link
-        run: cargo install flip-link
       - uses: actions/checkout@v3
       - uses: actions-rs/cargo@v1
         with:
           command: build
-      # no tests at the moment as the crate currently targets the stm32f4xx-hal and thus can't run on x86
+      - uses: actions-rs/cargo@v1
+        with:
+          command: check
+      - uses: actions-rs/cargo@v1
+        with:
+          command: test
       - uses: actions-rs/cargo@v1
         with:
           command: fmt
           args: --all -- --check
       - uses: actions-rs/cargo@v1
         with:
           command: clippy
+      - uses: actions-rs/cargo@v1
+        with:
+          command: audit