ci: Bump centos:stream8 to centos:stream9

This is required for the next commit. Also, drop CI_RETRY_EXE before
"dnf install", because it requires getopt, which will only be installed
later on via util-linux

ci/test/06_script_b.sh

@@ -52,7 +52,7 @@ fi
 
 if [ -z "$NO_DEPENDS" ]; then
   if [[ $CI_IMAGE_NAME_TAG == *centos* ]]; then
-    SHELL_OPTS="LC_ALL=en_US.UTF-8 CONFIG_SHELL=/bin/dash"
+    SHELL_OPTS="CONFIG_SHELL=/bin/dash"
   else
     SHELL_OPTS="CONFIG_SHELL="
   fi