CLDR-17088 Flesh out en.xml; new test for null/blank/inheritance-marker

[btangmu]

-New TestEnInheritance.java

CLDR-17088

• [ ] This PR completes the ticket.

ALLOW_MANY_COMMITS=true

[btangmu]

Locally this (first commit) results in these errors, and I expect it to have the same errors here:

[INFO] Running org.unicode.cldr.test.TestEnInheritance
Jan 08, 2024 1:07:39 PM org.unicode.cldr.test.TestEnInheritance complain
SEVERE: TestEnInheritance -- blank value 1 //ldml/personNames/nativeSpaceReplacement
Jan 08, 2024 1:07:39 PM org.unicode.cldr.test.TestEnInheritance complain
SEVERE: TestEnInheritance -- blank value 2 //ldml/personNames/foreignSpaceReplacement
Jan 08, 2024 1:07:39 PM org.unicode.cldr.test.TestEnInheritance complain
SEVERE: TestEnInheritance -- null value 1 //ldml/dates/timeZoneNames/metazone[@type="Gulf"]/short/standard
[ERROR] Tests run: 1, Failures: 1, Errors: 0, Skipped: 0, Time elapsed: 0.085 s <<< FAILURE! - in org.unicode.cldr.test.TestEnInheritance
[ERROR] org.unicode.cldr.test.TestEnInheritance.testEn  Time elapsed: 0.084 s  <<< FAILURE!
org.opentest4j.AssertionFailedError: null values ==> expected: <0> but was: <1>
	at org.junit.jupiter.api.AssertionUtils.fail(AssertionUtils.java:55)

The ticket specifies "blank" values as problematic, but maybe that's not to be taken literally, especially for nativeSpaceReplacement and foreignSpaceReplacement?

Also there's a null value for one path, the Gulf time zone.

There are no occurrences of INHERITANCE_MARKER (in Modern-coverage paths).

[btangmu]

Second commit running locally gets no more "blank" errors, still gets the Gulf time zone "null" error, and gets 155 new "null" errors for currencies including //ldml/numbers/currencies/currency[@type="BND"]/symbol

Still no INHERITANCE_MARKER errors

[macchiati]

Good. I'm a bit surprised we don't get more of the other items in CODE_FALLBACK besides currency, but that's good news.