[Playground] Remove Beam Summit banner from Playground

[miamihotline]

Removed Beam Summit banner from Playground header, deleted unused assets.

Fixes #22364

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[damondouglas]

@pabloem LGTM

[pabloem]

thanks y'\all lgtm

[brucearctor]

@pabloem --> Did this also address: #22424 ? Looks like that is no longer something that needs to be done, but trying to understand the code change that addressed it? If not this, can someone point me to the relevant issue to tag/close that issue ( to be able to easily restore in the future )?

[brucearctor]

@miamihotline -- did this code also address #22424 ? @damondouglas ( since approved ) maybe you have an idea?

Otherwise, wanting to track down how that got 'fixed' if not this issue. Please advise either way.

[olehborysevych]

@alexeyinkin could you please address comments above

[alexeyinkin]

The website banner was removed in 33dc35f