Python: Get rid of points-to from Definitions.qll

Turns out the `ImportTime` module (despite living in
`semmle.python.types` does not actually depend on points-to, so some of
the `LegacyPointsTo` imports could be replaced or removed.

python/ql/lib/LegacyPointsTo.qll

@@ -32,7 +32,6 @@ import semmle.python.types.FunctionObject
 import semmle.python.types.ModuleObject
 import semmle.python.types.Exceptions
 import semmle.python.types.Properties
-import semmle.python.types.ImportTime
 import semmle.python.types.Descriptors
 import semmle.python.SelfAttribute
 

python/ql/lib/analysis/DefinitionTracking.qll

@@ -4,6 +4,7 @@
 
 import python
 private import LegacyPointsTo
+private import semmle.python.types.ImportTime
 import IDEContextual
 
 private newtype TDefinition =

python/ql/lib/semmle/python/essa/Definitions.qll

@@ -11,7 +11,7 @@ import python
  * Escaping globals -- Global variables that have definitions and at least one of those definitions is in another scope.
  */
 
-private import LegacyPointsTo
+private import semmle.python.types.ImportTime
 private import semmle.python.essa.SsaDefinitions
 
 /** A source language variable, to be converted into a set of SSA variables. */

python/ql/src/Imports/Cyclic.qll

@@ -1,5 +1,6 @@
 import python
 private import LegacyPointsTo
+private import semmle.python.types.ImportTime
 
 predicate is_import_time(Stmt s) { not s.getScope+() instanceof Function }
 

python/ql/src/Imports/UnintentionalImport.ql

@@ -14,6 +14,7 @@
 
 import python
 private import LegacyPointsTo
+private import semmle.python.types.ImportTime
 
 predicate import_star(ImportStar imp, ModuleValue exporter) {
   exporter.importedAs(imp.getImportedModuleName())

python/ql/src/Variables/UndefinedGlobal.ql

@@ -12,6 +12,7 @@
 
 import python
 private import LegacyPointsTo
+private import semmle.python.types.ImportTime
 import Variables.MonkeyPatched
 import Loop
 

python/ql/src/Variables/UndefinedPlaceHolder.ql

@@ -14,6 +14,7 @@
 import python
 import Variables.MonkeyPatched
 private import LegacyPointsTo
+private import semmle.python.types.ImportTime
 
 /* Local variable part */
 predicate initialized_as_local(PlaceHolder use) {

python/ql/test/library-tests/PointsTo/general/GlobalPointsTo.ql

@@ -1,5 +1,6 @@
 import python
 private import LegacyPointsTo
+private import semmle.python.types.ImportTime
 import interesting
 
 from int line, ControlFlowNodeWithPointsTo f, Object o, ImportTimeScope n