feat: Extend reflexive methods with additional string operations (#1825)

* feat: extend reflexive methods with additional string operations

* fix(python): add missing dataflow source in TestPythonObjects snapshot

Author: ShakedPeretz

pkg/languages/python/analyzer/analyzer.go

@@ -15,6 +15,16 @@ var reflexiveMethods = []string{
 	"format",
 	"replace",
 	"split",
+	"lower",
+	"upper",
+	"strip",
+	"lstrip", 
+	"rstrip",
+	"capitalize",
+	"title",
+	"swapcase",
+	"casefold",
+	"expandtabs",
 }
 
 type analyzer struct {

pkg/languages/python/detectors/.snapshots/TestPythonObjects-object_class

@@ -319,6 +319,7 @@ children:
                                   id: 67
                                   range: 8:15 - 8:32
                                   dataflow_sources:
+                                    - 69
                                     - 75
                                   children:
                                     - type: attribute