ci/lava: Move LAVA dependencies to pip

Use requirements.txt and requirements-test.txt to organize better Python
dependencies related to LAVA.

Now LAVA tooling can use recent and fixed library versions.
And test-related libs will not trigger container rebuilding anymore.

Signed-off-by: Guilherme Gallo <guilherme.gallo@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/21325>

.gitlab-ci/container/debian/x86_build.sh

@@ -14,7 +14,6 @@ STABLE_EPHEMERAL=" \
       bzip2 \
       libtool \
       libssl-dev \
-      python3-pip \
       "
 
 apt-get update
@@ -43,8 +42,8 @@ apt-get install -y --no-remove \
       llvm-13-dev \
       llvm-11-dev \
       ocl-icd-opencl-dev \
-      python3-freezegun \
-      python3-pytest \
+      python3-pip \
+      python3-venv \
       procps \
       spirv-tools \
       shellcheck \
@@ -93,7 +92,7 @@ ninja install
 popd
 rm -rf DirectX-Headers
 
-pip3 install lavacli==1.5.2
+python3 -m pip install -r ${CI_PROJECT_DIR}/.gitlab-ci/lava/requirements.txt
 
 # install bindgen
 RUSTFLAGS='-L native=/usr/local/lib' cargo install \