Convert A27-0-4 to use the new dataflow library

Author: jketema

cpp/autosar/src/rules/A27-0-4/CStyleStringsUsed.ql

@@ -14,7 +14,7 @@
 
 import cpp
 import codingstandards.cpp.autosar
-import semmle.code.cpp.dataflow.DataFlow
+import semmle.code.cpp.dataflow.new.DataFlow
 
 class InstanceOfCStyleString extends Expr {
   InstanceOfCStyleString() {

cpp/autosar/test/rules/A27-0-4/CStyleStringsUsed.expected

@@ -1,6 +1,3 @@
-WARNING: module 'DataFlow' has been deprecated and may be removed in future (CStyleStringsUsed.ql:39,3-11)
-WARNING: module 'DataFlow' has been deprecated and may be removed in future (CStyleStringsUsed.ql:39,23-31)
-WARNING: module 'DataFlow' has been deprecated and may be removed in future (CStyleStringsUsed.ql:39,47-55)
 | test.cpp:7:20:7:27 | CodeQL | Usage of C-style string in $@. | test.cpp:7:20:7:27 | CodeQL | expression |
 | test.cpp:7:20:7:27 | CodeQL | Usage of C-style string in $@. | test.cpp:16:16:16:17 | a1 | expression |
 | test.cpp:8:22:8:26 | call to c_str | Usage of C-style string in $@. | test.cpp:8:22:8:26 | call to c_str | expression |