Rollup merge of #49176 - matthiaskrgr:config_example_rm_thinlto, r=alexcrichton
Rollup merge of #49176 - matthiaskrgr:config_example_rm_thinlto, r=alexcrichton

config.toml.example: thinlto bootstrap was removed

 It was removed in ff227c4a2d8a2fad5abf322f6f1391ae6779197f so remove the option that no longer works (we did not notice because it was commented out by default).

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