static Arguments fromEnvironment(UnaryOperator<String> getter, Supplier<Set<String>> keys) {
    return fromPrefixed(getter, keys, "PLANETILER", "_", true);
  }
Returns arguments parsed from environmental variables prefixed with {@code PLANETILER_}
<p>
For example to set {@code key=value}: {@code PLANETILER_KEY=value java -jar ...}
planetiler-core/src/main/java/com/onthegomap/planetiler/config/Arguments.java