Rollup merge of #78364 - XAMPPRocky:relnote-1.48.0, r=pietroalbini
Rollup merge of #78364 - XAMPPRocky:relnote-1.48.0, r=pietroalbini

Update RELEASES.md for 1.48.0

### [Rendered](https://github.com/XAMPPRocky/rust/blob/relnote-1.48.0/RELEASES.md)

r? `@Mark-Simulacrum`
cc `@rust-lang/release`

aidancully/rust,graydon/rust,aidancully/rust,graydon/rust,graydon/rust,graydon/rust,aidancully/rust,aidancully/rust,graydon/rust,aidancully/rust,graydon/rust,aidancully/rust