fix(complete): Deduplicate bash subcmd cases

**Problem:** Visible alias completions were causing duplicate case
conditions when offering subcommand completions, due to the fact that
they share the same function name as the command they are aliasing.

**Solution:** Deduplicate them so as to not redefine the exact same case
statement logic.

clap_complete/src/aot/shells/bash.rs

@@ -132,6 +132,7 @@ fn subcommand_details(cmd: &Command) -> String {
         .collect::<Vec<_>>();
 
     scs.sort();
+    scs.dedup();
 
     subcmd_dets.extend(scs.iter().map(|sc| {
         format!(

clap_complete/tests/snapshots/sub_subcommands.bash

@@ -152,20 +152,6 @@ _my-app() {
             COMPREPLY=( $(compgen -W "${opts}" -- "${cur}") )
             return 0
             ;;
-        my__app__some_cmd)
-            opts="-h -V --help --version sub_cmd help"
-            if [[ ${cur} == -* || ${COMP_CWORD} -eq 2 ]] ; then
-                COMPREPLY=( $(compgen -W "${opts}" -- "${cur}") )
-                return 0
-            fi
-            case "${prev}" in
-                *)
-                    COMPREPLY=()
-                    ;;
-            esac
-            COMPREPLY=( $(compgen -W "${opts}" -- "${cur}") )
-            return 0
-            ;;
         my__app__some_cmd__help)
             opts="sub_cmd help"
             if [[ ${cur} == -* || ${COMP_CWORD} -eq 3 ]] ; then