remove "pegasus: <version>" from tc when inlined in a workflow

When inline tc is serialized, "pegasus: <version>" needs to be removed. For example, this is how it is currently rendered when inlined in the workflow:

pegasus: "5.0"
x-pegasus:
  createdBy: "bamboo"
  createdOn: "today"
  apiLang: "java"
name: "test"
hooks:
  shell:
   -
    _on: "start"
    cmd: "cmd"
metadata:
  wf.api: "java"
replicaCatalog:
  replicas:
   -
    lfn: "f.a"
    pfns:
     -
      pfn: "file:///scratch/f.a"
      site: "local"
    metadata:
      foo: "bar"
      num: "1"
transformationCatalog:
  pegasus: "5.0" <---------------- needs to be removed
  transformations:
   -
    namespace: "pegasus"
    name: "analyze"
    version: "1.0"
    requires:
     - "pegasus::preprocess:1.0"