Rectify context name for using environments

[Corasonn]

Fixes the issue #187 context name in agent.context object always '-' when used with environments

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[Corasonn]

I signed it!

[googlebot]

CLAs look good, thanks!

[fgodino]

This is much needed! Please approve

[mhjb]

+1

[alexyoux]

+1

[nasirhm]

+1

[vverrastro]

Please could you merge and make a new public submission?
A lot of developers are waiting for this fix.

Thank you