chore: bump version to 2.0.91

update changelog to 2.0.91

Log: update changelog to 2.0.91

Author: mhduiy

debian/changelog

@@ -1,3 +1,13 @@
+dde-network-core (2.0.91) unstable; urgency=medium
+
+  * fix: prevent polkit popup when session is in background
+  * fix: disconnect D-Bus system bus connections in destructor before
+    thread exit
+  * fix: add per-device internet connectivity check for network
+    switching
+
+ -- zhangkun <zhangkun2@uniontech.com>  Thu, 11 Jun 2026 19:45:37 +0800
+
 dde-network-core (2.0.90) unstable; urgency=medium
 
   * fix: set alert duration to 2000ms and show error text