stream_bots: Display unsubscribe button on bots full profile modal.

Displaying unsubscribe button on bots full profile modal, allowing bot
owners to ubsubscribe their bots from streams.

Admins can also unsubscribe any bot from any subscribed streams from
bots full profile modal.

Fixes part of: #21402

frontend_tests/node_tests/people.js

@@ -316,6 +316,9 @@ test_people("basics", () => {
 
     assert.equal(people.get_bot_owner_user(bot_botson).full_name, "Isaac Newton");
 
+    assert.equal(people.can_admin_user(me), true);
+    assert.equal(people.can_admin_user(bot_botson), false);
+
     // Add our cross-realm bot.  It won't add to our human
     // count, and it has no owner.
     people.add_cross_realm_user(welcome_bot);

static/js/people.js

@@ -113,6 +113,13 @@ export function get_bot_owner_user(user) {
     return get_by_user_id(owner_id);
 }
 
+export function can_admin_user(user) {
+    return (
+        (user.is_bot && user.bot_owner_id && user.bot_owner_id === page_params.user_id) ||
+        is_my_user_id(user.user_id)
+    );
+}
+
 export function id_matches_email_operand(user_id, email) {
     const person = get_by_email(email);
 

static/js/user_profile.js

@@ -55,7 +55,7 @@ function initialize_bot_owner(element_id, bot_id) {
 
 function format_user_stream_list_item(stream, user) {
     const show_unsubscribe_button =
-        people.is_my_user_id(user.user_id) || settings_data.user_can_unsubscribe_other_users();
+        people.can_admin_user(user) || settings_data.user_can_unsubscribe_other_users();
     const show_private_stream_unsub_tooltip =
         people.is_my_user_id(user.user_id) && stream.invite_only;
     return render_user_stream_list_item({
@@ -252,7 +252,6 @@ function handle_remove_stream_subscription(target_user_id, sub, success, failure
             error: failure,
         });
     } else {
-        // Unsubscribed by admin.
         subscriber_api.remove_user_id_from_stream(target_user_id, sub, success, failure);
     }
 }