CI: quiche updates

- remove quiche from standard `linux` workflow
- add mod_h2 caching to quiche workflow
- rename quiche to quiche-linux
- move version definitions into env section

Closes #11528

.github/workflows/linux.yml

@@ -52,11 +52,6 @@ jobs:
       fail-fast: false
       matrix:
         build:
-        - name: quiche
-          install_packages: zlib1g-dev valgrind
-          install_steps: quiche pytest
-          configure: LDFLAGS="-Wl,-rpath,/home/runner/work/curl/curl/quiche/target/release" --with-openssl=/home/runner/work/curl/curl/quiche/quiche/deps/boringssl/src --enable-debug --with-quiche=/home/runner/work/curl/curl/quiche/target/release
-
         - name: bearssl
           install_packages: zlib1g-dev valgrind
           install_steps: bearssl pytest
@@ -201,27 +196,6 @@ jobs:
         make install
       name: 'install libressl'
 
-    - if: ${{ contains(matrix.build.install_steps, 'quiche') }}
-      run: |
-        git clone --quiet --depth=1 --recursive https://github.com/cloudflare/quiche.git
-        cd quiche
-        #### Work-around https://github.com/curl/curl/issues/7927 #######
-        #### See https://github.com/alexcrichton/cmake-rs/issues/131 ####
-        sed -i -e 's/cmake = "0.1"/cmake = "=0.1.45"/' quiche/Cargo.toml
-
-        # /home/runner/work/curl/curl/boringssl
-
-        cargo build -v --package quiche --release --features ffi,pkg-config-meta,qlog --verbose
-        mkdir -v quiche/deps/boringssl/src/lib
-        ln -vnf $(find target/release -name libcrypto.a -o -name libssl.a) quiche/deps/boringssl/src/lib/
-
-        # include dir
-        # /home/runner/work/curl/curl/quiche/quiche/deps/boringssl/src/include
-        # lib dir
-        # /home/runner/work/curl/curl/quiche/quiche/deps/boringssl/src/lib
-
-      name: 'build quiche and boringssl'
-
     - if: ${{ contains(matrix.build.install_steps, 'mbedtls') }}
       run: |
         git clone --quiet --depth=1 -b v3.3.0 https://github.com/ARMmbed/mbedtls