Release channel support - Update Release channel start page on March 4

[coreycb]

We are planning to switch the default download to the Release channel on March 4th, 2025 (136.0 release). This work will need to be timed to be published on the same day as the 136.0 release.

Since the Release channel will be supported as of March 4th, 2025, we will need to remove the warning from the Release channel start page.