dotkeeper v1.2.3

What's Changed

• docs: refresh README + site for v1.2 (subscriptions + offers) by @julian-corbet in #87
• chore: workflow hardening + Makefile help target (#82 feedback) by @julian-corbet in #88
• chore(alpine): first-class APKBUILD + GitHub Actions native build (#82) by @julian-corbet in #89

Full Changelog: v1.2.2...v1.2.3