Last of the three publishes that carry the checksum annotations from
3.0.0+up2026.8.2.java8, leaving main on the line of the only running server.
Same chart content as the java8 and java17 publishes, only the published Java
line changes: appVersion moves to the dated tag 2026.8.2-java21 and the
minecraft.version default moves to 1.21.1, the version ftb-skies-2 actually
runs (Java 8 runs up to 1.16.5, 1.18-1.20.4 need Java 17, 1.20.5+ need
Java 21).
Against the state before this series (2.0.0+up2026.8.2.java21) the only
replaced line in Chart.yaml and values.yaml is the chart version; appVersion
and the minecraft.version default are byte-identical, everything else is
additive.
Refs #82.
jklein
6543c6f02c