fix: urlencode email in reset password link (#15167)

Fixes https://github.com/coder/coder/issues/15151

This runs `urlencode` (provided by `text/template`) on the email address
in the link. This ensures the link will work if a user has an email in
the form `user+label@example.com`.

coderd/database/migrations/000267_fix_password_reset_notification_link.up.sql

@@ -0,0 +1,10 @@
+UPDATE notification_templates
+SET
+    title_template = E'Reset your password for Coder',
+    body_template = E'Hi {{.UserName}},\n\nUse the link below to reset your password.\n\nIf you did not make this request, you can ignore this message.',
+    actions = '[{
+		"label": "Reset password",
+		"url": "{{base_url}}/reset-password/change?otp={{.Labels.one_time_passcode}}&email={{.UserEmail | urlquery}}"
+	}]'::jsonb
+WHERE
+    id = '62f86a30-2330-4b61-a26d-311ff3b608cf'