Remove all mentions of supported browsers from the docs

Just remove all mentions of supported browsers from the docs.

In RNaKI section 1.2 we state that:

Red Hat will provide support for deployment, configuration, and use of the product.

OpenShift Dev Spaces 3.2 has been tested on Chrome version 101

.

There is no mention of Firefox; however, in User Guide section 9.4 we list 2 browsers:

Use a supported web browser:

• Google Chrome
• Mozilla Firefox

There is no mention of browser support in the Admin Guide.

Should we mention Chrome in the RN support policy section too?