tests/docker: fix mistakes in centos package lists

mesa-libEGL-devel is not used in QEMU at all, but mesa-libgbm-devel is.

spice-glib-devel is not use in QEMU at all, but spice-protocol is.
We also need the -devel package for spice-server, not the runtime.

There is no need to specifically refer to python36, we can just
use python3 as in other distros.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Wainer dos Santos Moschetta <wainersm@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20210623142245.307776-8-berrange@redhat.com>
Message-Id: <20210709143005.1554-16-alex.bennee@linaro.org>

tests/docker/dockerfiles/centos8.docker

@@ -21,16 +21,16 @@ ENV PACKAGES \
     libgcrypt-devel \
     lzo-devel \
     make \
-    mesa-libEGL-devel \
+    mesa-libgbm-devel \
     nettle-devel \
     ninja-build \
     nmap-ncat \
     perl-Test-Harness \
     pixman-devel \
-    python36 \
+    python3 \
     rdma-core-devel \
-    spice-glib-devel \
+    spice-protocol \
-    spice-server \
+    spice-server-devel \
     systemtap-sdt-devel \
     tar \
     zlib-devel