Run clippy across the whole workspace

A bunch of Clippy errors slipped in with kube-rs#653, which weren't picked up since
Clippy was set up to only cover the main `kube` crate.

Signed-off-by: Teo Klestrup Röijezon <teo@nullable.se>

.github/workflows/clippy.yml

@@ -8,9 +8,10 @@ jobs:
       - uses: actions/checkout@v2
       - uses: actions-rs/toolchain@v1
         with:
-            toolchain: nightly
-            components: clippy
-            override: true
+          toolchain: nightly
+          components: clippy
+          override: true
       - uses: actions-rs/clippy-check@v1
         with:
+          args: "--workspace"
           token: ${{ secrets.GITHUB_TOKEN }}