Tweak prepare.sh and specfile to make compatible with C8

ci/c8/prepare.sh

@@ -6,7 +6,7 @@ set -e
 ## step.
 ##------------------------------------------------------------------------------
 
-dnf install -y expect gcc-c++ cmake3 make rpm-build which git yum-plugin-priorities yum-utils libtsan dnf-plugins-core
+dnf install -y expect gcc-c++ cmake3 make rpm-build which git yum-utils libtsan dnf-plugins-core python3 epel-release
 
 ##------------------------------------------------------------------------------
 ## Extract quarkdb build dependencies from its specfile.

packaging/quarkdb.spec.in

@@ -34,7 +34,7 @@ BuildRequires: cmake3 >= 3.3
 %define cmake_cmd cmake3
 %endif
 BuildRequires: bzip2-devel
-BuildRequires: python
+BuildRequires: python3
 BuildRequires: zlib-static
 BuildRequires: zlib-devel
 BuildRequires: openssl-devel