Get rid of actions-rs/toolchain

Replaces 'actions-rs/toolchain' with bare `rustup` command, since this action haven't been updated in 2 years and `rustup` is included in GitHub Action's runner images.

See: https://github.com/actions/runner-images

.github/workflows/build-and-test.yml

@@ -24,12 +24,11 @@ jobs:
       - uses: actions/checkout@v3
       - uses: Swatinem/rust-cache@v2
       - name: Install Rust
-        uses: actions-rs/toolchain@v1
-        with:
-          toolchain: stable
-          profile: minimal
-          default: true
-          override: true
+        run: |
+          rustup set profile minimal
+          rustup toolchain install stable
+          rustup default stable
+          rustup override set stable
       - name: Build & Test (Default)
         run: cargo test --verbose --no-fail-fast
       - name: Build & Test (Default) - shadowsocks

.github/workflows/build-nightly-release.yml

@@ -21,13 +21,12 @@ jobs:
       - uses: actions/checkout@v3
 
       - name: Install Rust
-        uses: actions-rs/toolchain@v1
-        with:
-          profile: minimal
-          target: ${{ matrix.target }}
-          toolchain: stable
-          default: true
-          override: true
+        run: |
+          rustup set profile minimal
+          rustup toolchain install stable
+          rustup default stable
+          rustup override set stable
+          rustup target add --toolchain stable ${{ matrix.target }}
 
       - name: Setup Zig
         uses: goto-bus-stop/setup-zig@v2
@@ -82,13 +81,12 @@ jobs:
           echo "/usr/local/opt/gnu-tar/libexec/gnubin" >> $GITHUB_PATH
 
       - name: Install Rust
-        uses: actions-rs/toolchain@v1
-        with:
-          profile: minimal
-          target: ${{ matrix.target }}
-          toolchain: stable
-          default: true
-          override: true
+        run: |
+          rustup set profile minimal
+          rustup toolchain install stable
+          rustup default stable
+          rustup override set stable
+          rustup target add --toolchain stable ${{ matrix.target }}
 
       - name: Build release
         shell: bash
@@ -110,12 +108,11 @@ jobs:
       - uses: actions/checkout@v3
 
       - name: Install Rust
-        uses: actions-rs/toolchain@v1
-        with:
-          profile: minimal
-          toolchain: stable
-          default: true
-          override: true
+        run: |
+          rustup set profile minimal
+          rustup toolchain install stable
+          rustup default stable
+          rustup override set stable
 
       - name: Build release
         run: |

.github/workflows/build-release.yml

@@ -35,13 +35,12 @@ jobs:
       - uses: actions/checkout@v3
 
       - name: Install Rust
-        uses: actions-rs/toolchain@v1
-        with:
-          profile: minimal
-          target: ${{ matrix.target }}
-          toolchain: stable
-          default: true
-          override: true
+        run: |
+          rustup set profile minimal
+          rustup toolchain install stable
+          rustup default stable
+          rustup override set stable
+          rustup target add --toolchain stable ${{ matrix.target }}
 
       - name: Install cross
         run: cargo install cross
@@ -96,13 +95,12 @@ jobs:
           echo "/usr/local/opt/gnu-tar/libexec/gnubin" >> $GITHUB_PATH
 
       - name: Install Rust
-        uses: actions-rs/toolchain@v1
-        with:
-          profile: minimal
-          target: ${{ matrix.target }}
-          toolchain: stable
-          default: true
-          override: true
+        run: |
+          rustup set profile minimal
+          rustup toolchain install stable
+          rustup default stable
+          rustup override set stable
+          rustup target add --toolchain stable ${{ matrix.target }}
 
       - name: Build release
         shell: bash
@@ -126,12 +124,11 @@ jobs:
       - uses: actions/checkout@v3
 
       - name: Install Rust
-        uses: actions-rs/toolchain@v1
-        with:
-          profile: minimal
-          toolchain: stable
-          default: true
-          override: true
+        run: |
+          rustup set profile minimal
+          rustup toolchain install stable
+          rustup default stable
+          rustup override set stable
 
       - name: Build release
         run: |

.github/workflows/clippy-check.yml

@@ -24,13 +24,11 @@ jobs:
       - uses: actions/checkout@v3
       - uses: Swatinem/rust-cache@v2
       - name: Install Rust
-        uses: actions-rs/toolchain@v1
-        with:
-          toolchain: nightly
-          profile: minimal
-          components: clippy
-          default: true
-          override: true
+        run: |
+          rustup set profile minimal
+          rustup toolchain install nightly --component clippy
+          rustup default nightly
+          rustup override set nightly
       - name: Clippy Check
         uses: actions-rs/clippy-check@v1
         with: