Bug#907483: grub-efi-*-signed-template: `Built-Using` must refer to source packages

[Ansgar Burchardt]

Package: grub-efi-amd64-signed-template
Version: 2.02+dfsg1-5
Severity: serious

The `Built-Using` field of the source template refers to binary
packages instead of source packages.  This makes dak reject the upload
of the signed packages:

+---
| grub-efi-amd64-signed_1+2.02+dfsg1+5_amd64.deb: Built-Using refers to non-existing source package grub-efi-amd64-bin (= 2.02+dfsg1-5)
+---[ grub-efi-amd64-signed_1+2.02+dfsg1+5_amd64.changes.reason ]

(same for ia32/i386 and arm64)

Ansgar