Use nightly cargo to install cargo-cache

Stable cargo install still errors when packages exists, instead of updating it

Author: flip1995

.github/workflows/clippy.yml

@@ -93,6 +93,6 @@ jobs:
     # Cleanup
     - name: Run cargo-cache --autoclean
       run: |
-        cargo install cargo-cache --debug
+        cargo +nightly install cargo-cache --debug
         find ~/.cargo/bin ! -type d -exec strip {} \;
         cargo cache --autoclean

.github/workflows/clippy_bors.yml

@@ -161,7 +161,7 @@ jobs:
     # Cleanup
     - name: Run cargo-cache --autoclean
       run: |
-        cargo install cargo-cache --debug
+        cargo +nightly install cargo-cache --debug
         /usr/bin/find ~/.cargo/bin ! -type d -exec strip {} \;
         cargo cache --autoclean
       shell: bash
@@ -219,7 +219,7 @@ jobs:
     # Cleanup
     - name: Run cargo-cache --autoclean
       run: |
-        cargo install cargo-cache --debug
+        cargo +nightly install cargo-cache --debug
         find ~/.cargo/bin ! -type d -exec strip {} \;
         cargo cache --autoclean
   integration:
@@ -297,7 +297,7 @@ jobs:
     # Cleanup
     - name: Run cargo-cache --autoclean
       run: |
-        cargo install cargo-cache --debug
+        cargo +nightly install cargo-cache --debug
         find ~/.cargo/bin ! -type d -exec strip {} \;
         cargo cache --autoclean