[Publisher] On safari 13+, allow the user to publish H.265 streams

[dubeyShivank]

We have validated that H.265 streams can be published and viewed on safari with RTS, but it requires a bit of setup.

The scope of this ticket is to allow the publisher to select H.265 as the preferred codec if -

• The publisher is using Safari 13 or higher

The SDK should return H.265 when we query it for MediaCapabilities on Safari once the experimental feature flag is enabled.

[dubeyShivank]

Technically, this change has now been implemented in the SDK -> https://github.com/millicast/millicast-sdk/pull/233

When the SDK goes live next, the change will be published and H.265 will be available to safari users as a broadcasting option.