v1.26.0

version: minorMFW 2627 create & use credentials file (#142)

version: minor

* added credentials manager service

* add unit tests

* comments

* review changes

* credentials manager receives key from whoever calls it

* MFW-2248 Send alert command. Move logger mock to golang-shared testing package.

* use mutex on GetToken

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Co-authored-by: Varga Csaba <cvarga@arista.com>