Island: Fix string/bytes bug in StringListEncryptor

For some reason, bytes objects do not come out of mongo the same way
they go in. This class will be removed when reporting is reworked, so
rather than spend the time on figuring out exactly what's going on, just
use strings.

monkey/monkey_island/cc/models/report/report_dal.py

@@ -29,7 +29,8 @@ def save_report(report_dict: dict):
 
 def get_report() -> dict:
     report_dict = Report.objects.first().to_mongo()
-    return _decode_dot_char_before_mongo_insert(decrypt_dict(sensitive_fields, report_dict))
+    decrypted = decrypt_dict(sensitive_fields, report_dict)
+    return _decode_dot_char_before_mongo_insert(decrypted)
 
 
 # TODO remove this unnecessary encoding. I think these are legacy methods from back in the day

monkey/monkey_island/cc/server_utils/encryption/field_encryptors/string_list_encryptor.py

@@ -6,9 +6,9 @@ from . import IFieldEncryptor
 
 class StringListEncryptor(IFieldEncryptor):
     @staticmethod
-    def encrypt(value: List[str]):
-        return [get_datastore_encryptor().encrypt(string.encode()) for string in value]
+    def encrypt(value: List[str]) -> List[str]:
+        return [get_datastore_encryptor().encrypt(string.encode()).decode() for string in value]
 
     @staticmethod
-    def decrypt(value: List[bytes]):
-        return [get_datastore_encryptor().decrypt(bytes_).decode() for bytes_ in value]
+    def decrypt(value: List[str]) -> List[str]:
+        return [get_datastore_encryptor().decrypt(string.encode()).decode() for string in value]