Invalidate recipe's cache when dependant files changes

Recipes might depend on other files, like patches, so when
any of those changes, the recipe cache should be invalidated
too.
Fixes #91
7 jobs for issue-91 in 59 minutes and 32 seconds (queued for 3 minutes and 42 seconds)
Status Job ID Name Coverage
  Preparation
passed #77664
manifest

00:00:24

 
  Build
passed #77665
cerbero deps fedora x86_64

00:39:15

passed #77666
cerbero deps windows x86

00:36:40

passed #77667
cerbero deps windows x86_64

00:39:44

 
  Full Builds
passed #77669
build cerbero cross win32

00:14:26

passed #77670
build cerbero cross win64

00:14:39

passed #77668
build cerbero fedora x86_64

00:14:32