Add passing test struct_field_to_var_str for strings

tests/passing_tests/assign/struct_field_to_var_str.py

@@ -0,0 +1,26 @@
+from pythonbpf import bpf, struct, section, bpfglobal
+from pythonbpf.helper import comm
+
+from ctypes import c_void_p, c_int64
+
+
+@bpf
+@struct
+class data_t:
+    comm: str(16)  # type: ignore [valid-type]
+
+
+@bpf
+@section("tracepoint/syscalls/sys_enter_clone")
+def hello(ctx: c_void_p) -> c_int64:
+    dataobj = data_t()
+    comm(dataobj.comm)
+    strobj = dataobj.comm
+    print(f"clone called by comm {strobj}")
+    return 0
+
+
+@bpf
+@bpfglobal
+def LICENSE() -> str:
+    return "GPL"