[ImgBot] Optimize images

*Total -- 627.00kb -> 543.42kb (13.33%)

/repo-img/component-structure.png -- 20.36kb -> 10.52kb (48.35%)
/repo-img/sample-branch-selector.png -- 154.14kb -> 133.33kb (13.5%)
/repo-img/sample-std.png -- 113.55kb -> 99.29kb (12.56%)
/repo-img/sample-commit-selector.png -- 136.99kb -> 120.70kb (11.89%)
/repo-img/sample-raw-object-data.png -- 201.96kb -> 179.58kb (11.08%)

Signed-off-by: ImgBotApp <[email protected]>

Author: ImgBotApp