Revert "push: sign push if supported by remote" due to failing annex sync

This reverts commit bb309407676263c798831371fb594a256ea220f7.

> fatal: helper gcrypt does not support --signed=if-asked
>
>   Pushing to spicarium-bardum failed.

gitconfig

@@ -27,7 +27,6 @@
 
 [push]
 	default = simple
-	gpgSign = if-asked
 
 [tag]
 	forceSignAnnotated = true