[ImgBot] Optimize images (#280)

*Total -- 824.95kb -> 678.84kb (17.71%)

/static/img/png/shaft_bg.png -- 13.02kb -> 5.84kb (55.16%)
/static/img/png/logo.png -- 10.69kb -> 5.94kb (44.41%)
/static/img/png/shaft.png -- 10.69kb -> 5.94kb (44.41%)
/static/img/JIRA/Label.png -- 75.60kb -> 50.58kb (33.1%)
/static/img/JIRA/Generate_Token.png -- 57.95kb -> 39.47kb (31.89%)
/static/img/JIRA/Security_Tap.png -- 81.54kb -> 55.62kb (31.79%)
/static/img/JIRA/Create_API_Token.png -- 57.47kb -> 41.06kb (28.56%)
/static/img/JIRA/Account_settings.png -- 56.55kb -> 43.84kb (22.48%)
/docs/Getting_Started/screenshots/archetype.png -- 137.71kb -> 111.45kb (19.07%)
/static/img/png/selenium.png -- 15.76kb -> 12.76kb (19.02%)
/static/img/png/easy.png -- 24.10kb -> 22.58kb (6.32%)
/static/img/code.svg -- 6.69kb -> 6.68kb (0.19%)
/static/img/shaft_bg.svg -- 9.59kb -> 9.58kb (0.13%)
/static/img/logo.svg -- 9.50kb -> 9.49kb (0.09%)
/static/img/selenium.svg -- 21.59kb -> 21.58kb (0.06%)
/static/img/easy.svg -- 37.63kb -> 37.62kb (0.03%)
/static/img/shaft.svg -- 99.43kb -> 99.41kb (0.02%)
/static/img/shaft_white.svg -- 99.43kb -> 99.41kb (0.02%)

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

Author: imgbot[bot]