GHA: fix and tweak installed packages for http3-linux and Windows-cross

- explicitly install `libldap-dev` to not rely on test-specific packages
  installing it implicitly, to have the same `curl -V` output for each
  TLS backend build pair.
  Follow-up to 0455d8772a #18509

- install `libev-dev` for tests. It's a runtime dependency for
  the local build of `nghttpx`. Missing it made pytest skip 178 tests.
  Also skewing the 'Gain' time. I estimate it to account for 3 minutes,
  making the total gain ~20 minutes.
  Follow-up to 0455d8772a #18509
  (It may be a better solution to disable libev for the local nghttp2
  build, to avoid this hidden dependency.)

- fix quiche jobs to use the local build of `libnghttp2`.

- stop installing the `clang` package for Windows-cross. `clang` and
  `clang-tidy` tools are preinstalled on the Ubuntu 24.04 runner.

Closes #18519

.github/workflows/http3-linux.yml

@@ -476,6 +476,7 @@ jobs:
 
           - name: 'quiche'
             install_steps: skipall
+            PKG_CONFIG_PATH: /home/runner/nghttp2/build/lib/pkgconfig
             configure: >-
               LDFLAGS=-Wl,-rpath,/home/runner/quiche/target/release
               --with-openssl=/home/runner/quiche/quiche/deps/boringssl/src
@@ -484,7 +485,7 @@ jobs:
               --enable-unity
 
           - name: 'quiche'
-            PKG_CONFIG_PATH: /home/runner/quiche/target/release
+            PKG_CONFIG_PATH: /home/runner/nghttp2/build/lib/pkgconfig:/home/runner/quiche/target/release
             generate: >-
               -DOPENSSL_ROOT_DIR=/home/runner/quiche/quiche/deps/boringssl/src
               -DUSE_QUICHE=ON
@@ -495,7 +496,7 @@ jobs:
         env:
           INSTALL_PACKAGES: >-
             ${{ !contains(matrix.build.install_steps, 'skipall') && !contains(matrix.build.install_steps, 'skiprun') && 'stunnel4 ' || '' }}
-            ${{ !contains(matrix.build.install_steps, 'skipall') && !contains(matrix.build.install_steps, 'skiprun') && 'apache2 apache2-dev libnghttp2-dev vsftpd dante-server' || '' }}
+            ${{ !contains(matrix.build.install_steps, 'skipall') && !contains(matrix.build.install_steps, 'skiprun') && 'apache2 apache2-dev libnghttp2-dev vsftpd dante-server libev-dev' || '' }}
 
         run: |
           sudo rm -f /etc/apt/sources.list.d/microsoft-prod.list
@@ -503,7 +504,7 @@ jobs:
           sudo rm -f /var/lib/man-db/auto-update
           sudo apt-get -o Dpkg::Use-Pty=0 install \
             libtool autoconf automake pkgconf \
-            libpsl-dev libbrotli-dev libzstd-dev zlib1g-dev libidn2-0-dev libuv1-dev \
+            libpsl-dev libbrotli-dev libzstd-dev zlib1g-dev libidn2-0-dev libldap-dev libuv1-dev \
             ${INSTALL_PACKAGES} \
             ${MATRIX_INSTALL_PACKAGES}
           python3 -m venv ~/venv

.github/workflows/windows.yml

@@ -721,11 +721,9 @@ jobs:
           - { build: 'cmake'    , compiler: 'clang-tidy' }
     steps:
       - name: 'install packages'
-        env:
-          INSTALL_PACKAGES: ${{ matrix.compiler == 'clang-tidy' && 'clang' || '' }}
         run: |
           sudo rm -f /var/lib/man-db/auto-update
-          sudo apt-get -o Dpkg::Use-Pty=0 install gcc-mingw-w64-x86-64-win32 ${INSTALL_PACKAGES}
+          sudo apt-get -o Dpkg::Use-Pty=0 install gcc-mingw-w64-x86-64-win32
 
       - uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5
         with: