[Documentation] Specify version of HCLS API in Documentation

[svetakvsundhar]

Our current documentation does not specify the version of the HCLS API used when a client is created. This PR disambiguates the version by specifying v1 (v1beta1 will soon also be added).

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[svetakvsundhar]

R: @Abacn

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[Abacn]

LGTM