docs: update time zone in examples

Signed-off-by: simonsan <14062932+simonsan@users.noreply.github.com>

Author: simonsan

src/data_management/activity_log_storage.md

@@ -18,17 +18,17 @@ intermission:
 ```toml
 [01HQR3QRXEYK51T6N0D85G5668]
 description = "My Task"
-begin = "2024-02-28T16:01:13"
-end = "2024-02-28T16:02:40"
+begin = "2024-02-28T16:01:13+01:00"
+end = "2024-02-28T16:02:40+01:00"
 duration = 87
 kind = "activity"
 tags = ["test", "my", "lawn"]
 status = "ended"
 
 [01HQR3RTH6XJKMW4PFD2XFNK71]
 description = "My Task"
-begin = "2024-02-28T16:01:48"
-end = "2024-02-28T16:02:17"
+begin = "2024-02-28T16:01:48+01:00"
+end = "2024-02-28T16:02:17+01:00"
 duration = 29
 kind = "intermission"
 parent-id = "01HQR3QRXEYK51T6N0D85G5668"