Python: Adopt tests to new DataflowQueryTest

Co-authored-by: Rasmus Lerchedahl Petersen <yoff@github.com>

Author: RasmusWL

python/ql/test/experimental/query-tests/Security/CWE-022-UnsafeUnpacking/DataflowQueryTest.ql

@@ -1,3 +1,4 @@
 import python
 import experimental.dataflow.TestUtil.DataflowQueryTest
 import experimental.Security.UnsafeUnpackQuery
+import FromLegacyConfiguration<UnsafeUnpackingConfig>

python/ql/test/query-tests/Security/CWE-022-PathInjection/DataflowQueryTest.ql

@@ -1,3 +1,4 @@
 import python
 import experimental.dataflow.TestUtil.DataflowQueryTest
 import semmle.python.security.dataflow.PathInjectionQuery
+import FromLegacyConfiguration<Configuration>

python/ql/test/query-tests/Security/CWE-078-CommandInjection/DataflowQueryTest.ql

@@ -1,3 +1,4 @@
 import python
 import experimental.dataflow.TestUtil.DataflowQueryTest
 import semmle.python.security.dataflow.CommandInjectionQuery
+import FromLegacyConfiguration<Configuration>

python/ql/test/query-tests/Security/CWE-078-UnsafeShellCommandConstruction/DataflowQueryTest.ql

@@ -1,3 +1,4 @@
 import python
 import experimental.dataflow.TestUtil.DataflowQueryTest
 import semmle.python.security.dataflow.UnsafeShellCommandConstructionQuery
+import FromLegacyConfiguration<Configuration>