Pappas add FTHits dumper algorithm in the list

This MR adds the new dumper algorithm for dumping FTHits run3 data in JSON format for usage in Phoenix.

More information here: !993 (merged)

Depends on the MR in Rec: !2712

Hlt/RecoConf/python/RecoConf/phoenix_check.py

@@ -102,6 +102,18 @@ def hitsCheck(data_name, data):
             posAttributeCheck(it, data_name)
 
 
+def fibersCheck(data_name, data):
+    # check that hits is a list of objects containing proper attributes
+    if not isinstance(data, list):
+        raise PhoenixFormatError(
+            "Expected FTHits to be a list. Not the case for %s" % data_name)
+    for item in data:
+        if "x0" not in item or "y" not in item or "z0" not in item or "dxDy" not in item:
+            raise PhoenixFormatError(
+                "Expected FTHits to have x0, y0, y and dxDy as attributes. Not the case for %s"
+                % data_name)
+
+
 def clustersCheck(data_name, data):
     return
 
@@ -123,6 +135,7 @@ KnownDataTypes = {
     'Tracks': tracksCheck,
     'Clusters': clustersCheck,
     'Jets': jetsCheck,
+    'Fibers': fibersCheck,
     'Hits': hitsCheck,
     'Vertices': verticesCheck,
     'PlanarCaloCells': planarCaloCheck,