Extension Manager crashes after failing to load reviews

[dkvc]

Steps to Reproduce:

1. Open details of any extension in Extension Manager.
2. Open Show all reviews and close it before it loads/Crashes before loading reviews/Crashes while closing
3. The Extension Manager crashes.

Expected Behavior: Extension Manager shouldn't crash.

Probability of Occurrence of Bug: Common

System Information: OS: Fedora 36 Workstation Version: 0.4.0 Distribution Method: Flatpak

Stack Trace: ../src/exm-backtrace.c:78 'exm_backtrace_print' ../src/main.c:41 'handler' (null):0 '(null)' (null):0 '(null)' ../src/exm-comment-dialog.c:139 'on_get_comments' (null):0 '(null)' (null):0 '(null)' ../src/web/exm-request-handler.c:80 'request_callback' (null):0 '(null)' (null):0 '(null)' (null):0 '(null)' (null):0 '(null)' (null):0 '(null)' (null):0 '(null)' (null):0 '(null)' (null):0 '(null)' (null):0 '(null)' (null):0 '(null)' (null):0 '(null)' (null):0 '(null)' (null):0 '(null)' (null):0 '(null)' (null):0 '(null)' (null):0 '(null)' (null):0 '(null)' (null):0 '(null)' ../src/main.c:109 'run_app' (null):0 '(null)' (null):0 '(null)' ../sysdeps/x86_64/start.S:115 '(null)' (null):0 '(null)'

[oscfdezdz]

This crash is still present when opening and closing the dialog repeatedly when closing.