ccmlib/common: check install_dir/SCYLLA-VERSION-FILE first

we have some dtests which are marked with "dtest_enterprise" mark.
and they deselect themselves if ccm claims that the scylla build
is not enterprise.

sometimes, we just want to run some of these dtest right from local
build, whose SCYLLA-VERSION-FILE is co-located with the scylla
executable binary, right under the "install_dir" instead of
"install_dir/build/" or somewhere else. so, in this case, ccm
would either fail to find the right SCYLLA-VERSION-FILE, or
find a wrong one.

in this change, we add $install_dir/SCYLLA-VERSION-FILE at the
front of the check list, so that ccm can check and use it if
this file exists. this should address the pain of developers
who want to test from the local build.

Signed-off-by: Kefu Chai <[email protected]>

ccmlib/common.py

@@ -843,6 +843,7 @@ def get_version_from_build(install_dir=None, node_path=None):
 
 def _get_scylla_version(install_dir):
     scylla_version_files = [
+        os.path.join(install_dir, 'SCYLLA-VERSION-FILE'),
         os.path.join(install_dir, 'build', 'SCYLLA-VERSION-FILE'),
         os.path.join(install_dir, '..', '..', 'build', 'SCYLLA-VERSION-FILE'),
         os.path.join(install_dir, 'scylla-core-package', 'SCYLLA-VERSION-FILE'),