Make caching GitHub actions use separate caches (#35)

A follow-up to #34 
Once cache is formed, it's not updated anymore (see
actions/toolkit#505). As such, it doesn't make
sense having the cache shared between unrelated actions.
Made each action using a cache key tied to its tool.

Author: frozenspider

.github/workflows/coverage-pr.yml

@@ -97,8 +97,8 @@ jobs:
             ~/.cargo/registry/cache/
             ~/.cargo/git/db/
             target/
-          key: ${{ runner.os }}-cargo-${{ hashFiles('**/Cargo.lock') }}
-          restore-keys: ${{ runner.os }}-cargo-
+          key: ${{ runner.os }}-cargo-llvm-cov-${{ hashFiles('**/Cargo.lock') }}
+          restore-keys: ${{ runner.os }}-cargo-llvm-cov
 
       - name: Install cargo-llvm-cov (fallback path)
         if: ${{ steps.base_art.outputs.found == 'false' }}

.github/workflows/coverage.yml

@@ -25,8 +25,8 @@ jobs:
             ~/.cargo/registry/cache/
             ~/.cargo/git/db/
             target/
-          key: ${{ runner.os }}-cargo-${{ hashFiles('**/Cargo.lock') }}
-          restore-keys: ${{ runner.os }}-cargo-
+          key: ${{ runner.os }}-cargo-llvm-cov-${{ hashFiles('**/Cargo.lock') }}
+          restore-keys: ${{ runner.os }}-cargo-llvm-cov
 
       - run:  which cargo-llvm-cov || cargo install cargo-llvm-cov
       - run: rustup component add llvm-tools-preview

.github/workflows/dependency-audit.yml

@@ -32,8 +32,8 @@ jobs:
             ~/.cargo/registry/cache/
             ~/.cargo/git/db/
             target/
-          key: ${{ runner.os }}-cargo-${{ hashFiles('**/Cargo.lock') }}
-          restore-keys: ${{ runner.os }}-cargo-
+          key: ${{ runner.os }}-cargo-deny-${{ hashFiles('**/Cargo.lock') }}
+          restore-keys: ${{ runner.os }}-cargo-deny
 
       - name: Run audit-check action
         run: |

.github/workflows/semver-checks.yml

@@ -33,9 +33,9 @@ jobs:
           ~/.cargo/registry/index/
           ~/.cargo/registry/cache/
           ~/.cargo/git/db/
-        key: ${{ runner.os }}-cargo-${{ hashFiles('**/Cargo.lock') }}
+        key: ${{ runner.os }}-cargo-semver-checks-${{ hashFiles('**/Cargo.lock') }}
         restore-keys: |
-          ${{ runner.os }}-cargo-
+          ${{ runner.os }}-cargo-semver-checks
     
     - name: Get latest version tag
       id: get-baseline
@@ -79,4 +79,4 @@ jobs:
         echo "3. Future changes will be checked against tagged versions"
         echo ""
         echo "Note: Semver checking starts from v0.1.0 as this indicates"
-        echo "the beginning of API stability commitments in Rust projects"
+        echo "the beginning of API stability commitments in Rust projects"