don't write m_LastNetworkedValue on interp reset for predicted entities

[kusabana]

Description

PR #1392 made the predicted field m_vecPunchAngle interpolated which revealed an issue with interpolated, predicted fields:
when prediction fails, CInterpolatedVar::Reset copies the predicted punch angle into m_LastNetworkedValue

Interp_RestoreToLastNetworked writes m_LastNetworkedValue into m_vecPunchAngle, and OnStoreLastNetworkedValue writes m_vecPunchAngle back into m_LastNetworkedValue. The server only sends m_vecPunchAngle when it changes, so nothing corrects it and the view punch sticks until it changes again, like when firing a weapon.

[Tick 52114] 001 CPlayerLocalData::m_vecPunchAngle - vec[] differs (1st diff) (net 0.000000 0.000000 23.919640 - pred 0.000000 0.000000 23.700041) delta(0.000000 0.000000 -0.219599)
[Tick 52114] Full latch reset!

[Tick 52115] 001 CPlayerLocalData::m_vecPunchAngle - vec[] differs (1st diff) (net 0.000000 0.000000 23.919640 - pred 0.000000 0.000000 23.700041) delta(0.000000 0.000000 -0.219599)
[Tick 52115] Full latch reset!

...

This is especially an issue on community servers that opt to disable certain view punch effects like CGameMovement::PlayerRoughLandingEffects on the server, the client predicts it and gets stuck with the view punch.

This fixes the issue that people are experiencing on many CS:S bhop and surf servers right now.