Remove the integration test from the CI because of too much false failures

.github/workflows/ci.yml

@@ -37,32 +37,6 @@ jobs:
         with:
           command: test
           args: --verbose --all-features
-  integration-test:
-    name: Integration test
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v3
-      - name: Apt update
-        run: sudo apt update
-      - name: Install Python
-        run: sudo apt install -y python3
-      - name: Install OpenSMTPD
-        run: sudo apt install -y opensmtpd
-      - name: Stop OpenSMTPD
-        run: sudo systemctl stop opensmtpd.service
-      - name: Install Rust stable
-        uses: actions-rs/toolchain@v1
-        with:
-          toolchain: stable
-          override: true
-          profile: minimal
-      - name: Run cargo build
-        uses: actions-rs/cargo@v1
-        with:
-          command: build
-          args: --verbose --all-features
-      - name: Run the integration test
-        run: ./start_test.py
   cargo-fmt:
     name: Cargo fmt
     runs-on: ubuntu-latest