fix: NetworkManager.ShutdownInProgress not being reset (Unity-Technol…

…ogies#2661)

* fix

This resolves the issue where the NetworkManager.m_ShuttingDown property could be set to true again if the shutdown method is invoked within OnClientStopped or OnServerStopped.

* test

This validates that if you invoke shutdown within OnClientStopped or OnServerStopped that NetworkManager.ShutdownInProgress remains false once completing the shutdown process.

* update

Adding the changelog entry for this fix.
Making the changelog entry for v1.6.0 branch match Unity-Technologies#2657

* Update CHANGELOG.md

Removing the adjusted changelog entry

chore: tagging 1.5.2 in the changelog (Unity-Technologies#2640)

fix: Presence of NetworkVariable<T>[] in a class causes an exception (U…

…nity-Technologies#2584)

fixes Unity-Technologies#2576

chore: Update UTP dependency to 1.3.4 (Unity-Technologies#2533)

chore: 1.3.1 version update (Unity-Technologies#2477)

chore: Bump version to 1.3.1

chore: Ignore BasicBuildTest on release/1.2.0 (Unity-Technologies#2339)

chore: update changelog for 1.1 (Unity-Technologies#2264)

chore: Hotfix - bump 1.0.2 and run tests (Unity-Technologies#2182)

Bump version to 1.0.2 and update changelog

chore: Bump NGO version to 1.0.1 (Unity-Technologies#2131)

chore: Bump NGO version to 1.0.1 (Unity-Technologies#2131)