C#: Remove reference to the deleted api.

Author: aschackmull

csharp/ql/lib/experimental/code/csharp/Cryptography/NonCryptographicHashes.qll

@@ -8,7 +8,6 @@
 
 import csharp
 private import DataFlow
-private import semmle.code.csharp.dataflow.TaintTracking2
 
 predicate maybeANonCryptographicHash(
   Callable callable, Variable v, Expr xor, Expr mul, LoopStmt loop

csharp/ql/lib/semmle/code/csharp/frameworks/Format.qll

@@ -5,7 +5,6 @@
 import csharp
 private import semmle.code.csharp.frameworks.System
 private import semmle.code.csharp.frameworks.system.Text
-private import semmle.code.csharp.dataflow.DataFlow2
 
 /** A method that formats a string, for example `string.Format()`. */
 class FormatMethod extends Method {

csharp/ql/lib/semmle/code/csharp/frameworks/Sql.qll

@@ -6,7 +6,6 @@ private import semmle.code.csharp.frameworks.system.data.SqlClient
 private import semmle.code.csharp.frameworks.EntityFramework
 private import semmle.code.csharp.frameworks.NHibernate
 private import semmle.code.csharp.frameworks.Dapper
-private import semmle.code.csharp.dataflow.DataFlow4
 
 /** An expression containing a SQL command. */
 abstract class SqlExpr extends Expr {

csharp/ql/lib/semmle/code/csharp/frameworks/system/Xml.qll

@@ -2,7 +2,6 @@
 
 import csharp
 private import semmle.code.csharp.frameworks.System
-private import semmle.code.csharp.dataflow.DataFlow3
 
 /** The `System.Xml` namespace. */
 class SystemXmlNamespace extends Namespace {

csharp/ql/lib/semmle/code/csharp/security/dataflow/ReDoSQuery.qll

@@ -4,7 +4,6 @@
  */
 
 import csharp
-private import semmle.code.csharp.dataflow.DataFlow2
 private import semmle.code.csharp.security.dataflow.flowsinks.FlowSinks
 private import semmle.code.csharp.security.dataflow.flowsources.FlowSources
 private import semmle.code.csharp.frameworks.system.text.RegularExpressions

csharp/ql/lib/semmle/code/csharp/security/dataflow/UnsafeDeserializationQuery.qll

@@ -5,7 +5,6 @@
 
 import csharp
 private import semmle.code.csharp.serialization.Deserializers
-private import semmle.code.csharp.dataflow.TaintTracking2
 private import semmle.code.csharp.security.dataflow.flowsinks.FlowSinks
 private import semmle.code.csharp.security.dataflow.flowsources.FlowSources
 

csharp/ql/lib/semmle/code/csharp/security/dataflow/XSSQuery.qll

@@ -7,8 +7,6 @@ import csharp
 private import XSSSinks
 private import semmle.code.csharp.security.Sanitizers
 private import semmle.code.csharp.security.dataflow.flowsources.FlowSources
-private import semmle.code.csharp.dataflow.DataFlow2
-private import semmle.code.csharp.dataflow.TaintTracking2
 
 /**
  * Holds if there is tainted flow from `source` to `sink` that may lead to a

csharp/ql/lib/semmle/code/csharp/security/xml/InsecureXMLQuery.qll

@@ -150,8 +150,6 @@ module XmlSettings {
 
 /** Provides predicates related to `System.Xml.XmlReader`. */
 module XmlReader {
-  private import semmle.code.csharp.dataflow.DataFlow2
-
   private class InsecureXmlReaderCreate extends InsecureXmlProcessing, MethodCall {
     InsecureXmlReaderCreate() {
       this.getTarget().hasFullyQualifiedName("System.Xml.XmlReader", "Create")