feat(bira): add support for `kube-ps1` prompt (#8437)

themes/bira.zsh-theme

@@ -6,10 +6,15 @@ local current_dir="%B%{$fg[blue]%}%~ %{$reset_color%}"
 local vcs_branch='$(git_prompt_info)$(hg_prompt_info)'
 local rvm_ruby='$(ruby_prompt_info)'
 local venv_prompt='$(virtualenv_prompt_info)'
+if [[ "${plugins[@]}" =~ 'kube-ps1' ]]; then
+    local kube_prompt='$(kube_ps1)'
+else
+    local kube_prompt=''
+fi
 
 ZSH_THEME_RVM_PROMPT_OPTIONS="i v g"
 
-PROMPT="╭─${user_host}${current_dir}${rvm_ruby}${vcs_branch}${venv_prompt}
+PROMPT="╭─${user_host}${current_dir}${rvm_ruby}${vcs_branch}${venv_prompt}${kube_prompt}
 ╰─%B${user_symbol}%b "
 RPROMPT="%B${return_code}%b"