Add extra dependencies needed by the gating test

tests/tests.yml

@@ -4,8 +4,14 @@
     tags:
     - classic
     required_packages:
-    - coreutils
     - virt-p2v
+    # https://github.com/libguestfs/virt-p2v/blob/master/dependencies.m4
+    # Only need the virt-p2v program dependencies.
+    # There's no way that I'm aware of to build this list automatically.
+    - dbus-libs
+    - gtk3
+    - libxml2
+    - pcre2
     tests:
     - simple:
         dir: .