Rollup merge of #81771 - tgnottingham:time-passes-rss-delta, r=oli-obk
Rollup merge of #81771 - tgnottingham:time-passes-rss-delta, r=oli-obk

Indicate change in RSS from start to end of pass in time-passes output

Previously, this was omitted because it could be misleading, but the
functionality seems too useful not to include.

r? ``@oli-obk``

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