Rollup merge of #141771 - Kobzol:bors-increase-timeout, r=marcoieni

Increase timeout for new bors try builds

To sync it with [homu](https://github.com/rust-lang/homu/blob/master/cfg.production.toml#L34). Saw the timeout [here](rust-lang/rust#138699 (comment)), it was set to only 4 hours for new bors.

r? ``@marcoieni``

Author: workingjubilee