(PA-7110) Fix centos downcase bug

Author: shubhamshinde360

spec/spec_helper_acceptance_local.rb

@@ -42,7 +42,7 @@ def iptables_version
 def pre_setup
   LitmusHelper.instance.run_shell('mkdir -p /lib/modules/`uname -r`')
   LitmusHelper.instance.run_shell('yum install module-init-tools -y') if fetch_os_name == 'rocky'
-  LitmusHelper.instance.run_shell('dnf install -y kmod') if fetch_os_name == 'CentOS' && fetch_os_version == '9'
+  LitmusHelper.instance.run_shell('dnf install -y kmod') if fetch_os_name == 'centos' && fetch_os_version == '9'
   LitmusHelper.instance.run_shell('depmod -a')
 end