test(regexp): enable duplicate named capturing groups tests

[tkshsbcue]

test(regexp): enable duplicate named capturing groups tests

Closes #4442.

The regress crate v0.11.1 (already in our dependencies) supports duplicate named capturing groups. This removes the feature skip and individual test skip that were blocking test262 coverage for this Stage 4 proposal.

Changes

• Remove "regexp-duplicate-named-groups" from ignored features in test262_config.toml
• Remove the non-unicode-property-names-valid.js test skip (its TODO comment says to remove once regress fixes named groups parsing, which v0.11 did)

The SpecEdition::ES16 mapping in edition.rs was already in place.

[github-actions]

Test262 conformance changes

Test result	main count	PR count	difference
Total	53,125	53,125	0
Passed	51,049	51,063	+14
Ignored	1,482	1,462	-20
Failed	594	600	+6
Panics	0	0	0
Conformance	96.09%	96.12%	+0.03%

Fixed tests (14):

test/staging/built-ins/RegExp/named-groups/duplicate-named-groups-search.js (previously Ignored)
test/built-ins/String/prototype/match/duplicate-named-groups-properties.js (previously Ignored)
test/built-ins/String/prototype/match/duplicate-named-indices-groups-properties.js (previously Ignored)
test/built-ins/RegExp/duplicate-named-capturing-groups-syntax.js (previously Ignored)
test/built-ins/RegExp/named-groups/duplicate-names-replace.js (previously Ignored)
test/built-ins/RegExp/named-groups/duplicate-names-match-indices.js (previously Ignored)
test/built-ins/RegExp/named-groups/duplicate-names-split.js (previously Ignored)
test/built-ins/RegExp/named-groups/duplicate-names-group-property-enumeration-order.js (previously Ignored)
test/built-ins/RegExp/named-groups/duplicate-names-search.js (previously Ignored)
test/built-ins/RegExp/named-groups/duplicate-names-replaceall.js (previously Ignored)
test/built-ins/RegExp/named-groups/duplicate-names-matchall.js (previously Ignored)
test/built-ins/RegExp/prototype/exec/duplicate-named-groups-properties.js (previously Ignored)
test/built-ins/RegExp/prototype/exec/duplicate-named-indices-groups-properties.js (previously Ignored)
test/annexB/built-ins/RegExp/prototype/compile/duplicate-named-capturing-groups-syntax.js (previously Ignored)

Tested main commit: 3cec5e6bc4454077cb8d65b537d368d633137e0e
Tested PR commit: 4c64386c9f84cd489c814d33086484069fe15e7f
Compare commits: 3cec5e6...4c64386

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 59.78%. Comparing base (6ddc2b4) to head (4c64386).
⚠️ Report is 951 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff             @@
##             main    #5327       +/-   ##
===========================================
+ Coverage   47.24%   59.78%   +12.54%     
===========================================
  Files         476      590      +114     
  Lines       46892    63695    +16803     
===========================================
+ Hits        22154    38080    +15926     
- Misses      24738    25615      +877     

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[jedel1043]

Duplicate of #4550

[tkshsbcue]

sorry my bad i thought this could be better implementation