fix: typo in {bash,zsh}_completions.go (#1459)

* Fix typo in bash_completions.go
* Fix the same typo in zsh_completions.go

bash_completions.go

@@ -134,7 +134,7 @@ __%[1]s_handle_go_custom_completion()
         $filteringCmd
     elif [ $((directive & shellCompDirectiveFilterDirs)) -ne 0 ]; then
         # File completion for directories only
-        local subDir
+        local subdir
         # Use printf to strip any trailing newline
         subdir=$(printf "%%s" "${out[0]}")
         if [ -n "$subdir" ]; then

zsh_completions.go

@@ -202,7 +202,7 @@ _%[1]s()
         _arguments '*:filename:'"$filteringCmd"
     elif [ $((directive & shellCompDirectiveFilterDirs)) -ne 0 ]; then
         # File completion for directories only
-        local subDir
+        local subdir
         subdir="${completions[1]}"
         if [ -n "$subdir" ]; then
             __%[1]s_debug "Listing directories in $subdir"