No bug: [try-staging] Don't generate versions with `esr` in them; r=nthomas

Balrog accepts them, but then fails to serve them.

Differential Revision: https://phabricator.services.mozilla.com/D11390

--HG--
extra : moz-landing-system : lando

tools/tryselect/selectors/release.py

@@ -64,10 +64,7 @@ def run_try_release(
     push=True, message='{msg}', **kwargs
 ):
 
-    if version.is_beta:
-        app_version = attr.evolve(version, beta_number=None)
-    else:
-        app_version = version
+    app_version = attr.evolve(version, beta_number=None, is_esr=False)
 
     files_to_change = {
         'browser/config/version.txt': '{}\n'.format(app_version),