Release new version 0.93

Quoting from https://packages.qa.debian.org/g/grml-debootstrap.html

| Issues preventing migration:
| Not built on buildd: arch all binaries uploaded by mika, a new source-only upload is needed to allow migration

Sigh...

debian/changelog

@@ -1,3 +1,9 @@
+grml-debootstrap (0.93) unstable; urgency=medium
+
+  * New release (without code changes) to fix Debian policy issue
+
+ -- Michael Prokop <mika@grml.org>  Fri, 05 Jun 2020 14:14:44 +0200
+
 grml-debootstrap (0.92) unstable; urgency=medium
 
   [ Antoine Beaupré ]