ref(trace-details): Remove replacement attribute filtering when conventions flag is off

[obostjancic]

Summary

• Stacked on fix(trace-details): Show replacement attributes when no deprecated source exists #114943
• Removes the is_sentry_convention_replacement_attribute filtering entirely from the else branch (when use_sentry_conventions is off)
• With the conventions flag at 0% rollout, this filtering was the sole cause of replacement attributes being invisible in span details
• Showing both deprecated and new names (minor duplication) is better than silently dropping data

[github-actions]

Backend Test Failures

Failures on 24e6486 in this run:

tests/snuba/api/endpoints/test_project_trace_item_details.py::ProjectTraceItemDetailsEndpointTest::test_simple_using_spans_item_type — log

[gw1] linux -- Python 3.13.1 /home/runner/work/sentry/sentry/.venv/bin/python3
tests/snuba/api/endpoints/test_project_trace_item_details.py:259: in test_simple_using_spans_item_type
    assert trace_details_response.data["attributes"] == [
E   AssertionError: assert [{'name': 'is...144.287}, ...] == [{'name': 'is...1.8e+03}, ...]
E     
E     At index 2 diff: {'name': 'http.response.body.size', 'type': 'float', 'value': 100.0} != {'name': 'http.response_content_length', 'type': 'float', 'value': 100.0}
E     Left contains one more item: {'name': 'transaction.span_id', 'type': 'str', 'value': '56157853078e4bc7'}
E     
E     Full diff:
E       [
E           {
E               'name': 'is_transaction',
E               'type': 'bool',
E               'value': False,
E           },
E           {
E               'name': 'code.lineno',
E               'type': 'float',
E               'value': 420.0,
E           },
E           {
E     +         'name': 'http.response.body.size',
E     +         'type': 'float',
E     +         'value': 100.0,
E     +     },
E     +     {
E               'name': 'http.response_content_length',
E               'type': 'float',
E               'value': 100.0,
E           },
E           {
E               'name': 'precise.finish_ts',
E               'type': 'float',
E     -         'value': 1778054144.287 ± 1.8e+03,
E     ?                           ^    ----------
E     +         'value': 1778054145.287,
E     ?                           ^
E           },
E           {
E               'name': 'precise.start_ts',
E               'type': 'float',
E     -         'value': 1778054144.287 ± 1.8e+03,
E     ?                                ----------
E     +         'value': 1778054144.287,
E           },
E           {
E               'name': 'received',
E               'type': 'float',
E     -         'value': 1778054144.287 ± 1.8e+03,
E     ?                                ----------
... (68 more lines)