Fix crash that could occur if closing the usercard quickly after blocking (#4711)

* Specifically, this adds a caller to the network request, which makes the
success or failure callback not fire.
This has the unintended consequence of the block list not reloading if
the usercard is closed, but it's not a big concern.

* Add unrelated `-DUSE_ALTERNATE_LINKER` cmake option

From https://github.com/heavyai/heavydb/blob/0517d99b467806f6af7b4c969e351368a667497d/CMakeLists.txt#L87-L103

CHANGELOG.md

@@ -16,6 +16,7 @@
 - Bugfix: Fix visual glitches with smooth scrolling. (#4501)
 - Bugfix: Fixed pings firing for the "Your username" highlight when not signed in. (#4698)
 - Bugfix: Fixed partially broken filters on Qt 6 builds. (#4702)
+- Bugfix: Fixed crash that could occurr when closing the usercard too quickly after blocking or unblocking a user. (#4711)
 - Dev: Added command to set Qt's logging filter/rules at runtime (`/c2-set-logging-rules`). (#4637)
 - Dev: Added the ability to see & load custom themes from the Themes directory. No stable promises are made of this feature, changes might be made that breaks custom themes without notice. (#4570)
 - Dev: Added test cases for emote and tab completion. (#4644)
@@ -30,6 +31,7 @@
 - Dev: Added `sccache` in Windows CI. (#4678)
 - Dev: Moved preprocessor Git and date definitions to executables only. (#4681)
 - Dev: Refactored tests to be able to use `ctest` and run in debug builds. (#4700)
+- Dev: Added the ability to use an alternate linker using the `-DUSE_ALTERNATE_LINKER=...` CMake parameter. (#4711)
 
 ## 2.4.4