[z1963] Replace an ASSERT to prevent unnecessairy crashes

GetAngle can be called for self from very many places, not only DB-errors, hence adding the assert is too strong in the moment

Signed-off-by: Schmoozerd <schmoozerd@scriptdev2.com>
Signed-off-by: Nighoo <nighoo@gmail.com>

(based on commit 2f03b28)

(based on commit [s1551] - f15345e)