[ImgBot] Optimize images

*Total -- 2,399.60kb -> 2,070.24kb (13.73%)

/doc/source/images/add-trigger1.png -- 85.46kb -> 53.36kb (37.56%)
/doc/source/images/pipeline-run.png -- 73.89kb -> 47.30kb (35.98%)
/doc/source/images/flow.png -- 35.37kb -> 22.91kb (35.23%)
/doc/source/images/argocd.png -- 106.62kb -> 70.10kb (34.25%)
/doc/source/images/argo-app.png -- 178.48kb -> 117.56kb (34.13%)
/doc/source/images/add-trigger.png -- 75.48kb -> 50.45kb (33.16%)
/doc/source/images/add-webhook.png -- 76.69kb -> 51.48kb (32.87%)
/doc/source/images/webhook-set.png -- 42.29kb -> 30.00kb (29.07%)
/doc/source/images/sample-output.png -- 156.03kb -> 113.20kb (27.45%)
/doc/source/images/copy-trigger-link.gif -- 293.63kb -> 281.53kb (4.12%)
/doc/source/images/pipeline-build.gif -- 812.27kb -> 782.13kb (3.71%)
/doc/source/images/pipeline-details.gif -- 463.39kb -> 450.23kb (2.84%)

Signed-off-by: ImgBotApp <ImgBotHelp@gmail.com>

Author: ImgBotApp