ENH: unify use of dictionary method names

- previously introduced `getOrDefault` as a dictionary _get_ method,
  now complete the transition and use it everywhere instead of
  `lookupOrDefault`. This avoids mixed usage of the two methods that
  are identical in behaviour, makes for shorter names, and promotes
  the distinction between "lookup" access (ie, return a token stream,
  locate and return an entry) and "get" access (ie, the above with
  conversion to concrete types such as scalar, label etc).

src/functionObjects/utilities/runTimeControl/runTimeControl.C

@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2015 OpenFOAM Foundation
-    Copyright (C) 2015-2018 OpenCFD Ltd.
+    Copyright (C) 2015-2020 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -155,7 +155,7 @@ bool Foam::functionObjects::runTimeControls::runTimeControl::read
         // Set the action to perform when all conditions are satisfied
         // - set to end for backwards compatibility with v1806
         satisfiedAction_ =
-            satisfiedActionNames.lookupOrDefault
+            satisfiedActionNames.getOrDefault
             (
                 "satisfiedAction",
                 dict,