Fix typo in footer: update year to 2023#44689

Maithili-Badhan wants to merge 1 commit intoibm-developer-skills-network:masteribm-developer-skills-network/jbbmo-Introduction-to-Git-and-GitHub:masterfrom

Maithili-Badhan:bug-fix-revertMaithili-Badhan/jbbmo-Introduction-to-Git-and-GitHub:bug-fix-revertCopy head branch name to clipboard