Fix interrupted cache dir for projects without a version

rbm.conf

@@ -506,13 +506,13 @@ runc:
     set -e
 
     # Handle SIGINT case
-    if [ -d '[% c("rbm_tmp_dir") %]'/../interrupted_dirs/'[% c("var/build_id") %]' ]
+    if [ -d '[% c("rbm_tmp_dir") %]'/../interrupted_dirs/'[% sha256(dest_dir _ '/' _ c("filename")) %]' ]
     then
         # We previously did this build but it was manually interrupted.
         # Restore the container's saved state instead of making a new container.
         mkdir -p '[% c("var/container/dir") %]'
         rmdir '[% c("var/container/dir") %]'
-        mv '[% c("rbm_tmp_dir") %]'/../interrupted_dirs/'[% c("var/build_id") %]' '[% c("var/container/dir") %]'
+        mv '[% c("rbm_tmp_dir") %]'/../interrupted_dirs/'[% sha256(dest_dir _ '/' _ c("filename")) %]' '[% c("var/container/dir") %]'
         exit
     fi
 
@@ -600,7 +600,7 @@ runc:
         # Save the container's state instead of deleting, so we can resume 
         # the build later.
         mkdir -p '[% c("rbm_tmp_dir") %]'/../interrupted_dirs
-        mv '[% c("var/container/dir") %]' '[% c("rbm_tmp_dir") %]'/../interrupted_dirs/'[% c("var/build_id") %]'
+        mv '[% c("var/container/dir") %]' '[% c("rbm_tmp_dir") %]'/../interrupted_dirs/'[% sha256(dest_dir _ '/' _ c("filename")) %]'
         rm '[% c("rbm_tmp_dir") %]'/../interrupted
         exit
     fi