2.59.0 Beam site updates.

[lostluck]

Update the Beam site pages with the 2.59.0 release, targeted for 2024-08-28.

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[github-actions[bot]]

Assigning reviewers. If you would like to opt out of this review, comment assign to next reviewer:

R: @kennknowles for label website.

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[github-actions[bot]]

Reminder, please take a look at this pr: @kennknowles

[github-actions[bot]]

Assigning new set of reviewers because Pr has gone too long without review. If you would like to opt out of this review, comment assign to next reviewer:

R: @melap for label website.

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[github-actions[bot]]

Reminder, please take a look at this pr: @melap