Updating programs and stats page

[nate-double-u]

• adding completed lfx 2023 term 2 projects to mentoring/programs page
• updating overall stats on home page
• some cleanup

[nate-double-u]

preview:

• https://github.com/nate-double-u/cncf-mentoring/tree/update-lfx-2023-term2-statistics
• https://github.com/nate-double-u/cncf-mentoring/tree/update-lfx-2023-term2-statistics/programs

[nate-double-u]

Setting DCO to pass as we'll squash the commits.