Remove two recently-added, unused needles

Lukas added these in a recent big commit that fixed problems with
GNOME 45, I think these two were probably needles from some
in-development tests that are not actually needed in prod yet.
They make the tests fail, so we need to get rid of them.

Signed-off-by: Adam Williamson <awilliam@redhat.com>

needles/gnome/apps/dialogue_third_party_repos.json

@@ -1,15 +0,0 @@
-{
-  "area": [
-    {
-      "xpos": 445,
-      "ypos": 292,
-      "width": 109,
-      "height": 27,
-      "type": "match"
-    }
-  ],
-  "properties": [],
-  "tags": [
-    "dialogue_third_party_repos"
-  ]
-}

needles/gnome/apps/gnome_button_ignore.json

@@ -1,15 +0,0 @@
-{
-  "area": [
-    {
-      "xpos": 385,
-      "ypos": 499,
-      "width": 53,
-      "height": 27,
-      "type": "match"
-    }
-  ],
-  "properties": [],
-  "tags": [
-    "gnome_button_ignore"
-  ]
-}