[9.0] [A11y][APM] Add aria-label to latency selector in service overview (#215644) (#215695)

# Backport

This will backport the following commits from `main` to `9.0`:
- [[A11y][APM] Add `aria-label` to latency selector in service overview
(#215644)](https://github.com/elastic/kibana/pull/215644)

<!--- Backport version: 9.6.6 -->

### Questions ?
Please refer to the [Backport tool
documentation](https://github.com/sorenlouv/backport)

<!--BACKPORT [{"author":{"name":"Sergi
Romeu","email":"sergi.romeu@elastic.co"},"sourceCommit":{"committedDate":"2025-03-24T12:54:17Z","message":"[A11y][APM]
Add `aria-label` to latency selector in service overview (#215644)\n\n##
Summary\n\nFixes #210270\n\nThis PR adds an `aria-label` to solve the
\"Element missing an accessible\nname\" A11y critical issue.\n\n## How
to test\n1. Download the
[axe\ndevtools](https://chromewebstore.google.com/detail/axe-devtools-web-accessib/lhdoppojpmngadmnindnejefpokejbdd)\n2.
Go into a service overview and run the scanner from axe devtools\n3. You
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Add `aria-label` to latency selector in service
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Add `aria-label` to latency selector in service overview (#215644)\n\n##
Summary\n\nFixes #210270\n\nThis PR adds an `aria-label` to solve the
\"Element missing an accessible\nname\" A11y critical issue.\n\n## How
to test\n1. Download the
[axe\ndevtools](https://chromewebstore.google.com/detail/axe-devtools-web-accessib/lhdoppojpmngadmnindnejefpokejbdd)\n2.
Go into a service overview and run the scanner from axe devtools\n3. You
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Add `aria-label` to latency selector in service overview (#215644)\n\n##
Summary\n\nFixes #210270\n\nThis PR adds an `aria-label` to solve the
\"Element missing an accessible\nname\" A11y critical issue.\n\n## How
to test\n1. Download the
[axe\ndevtools](https://chromewebstore.google.com/detail/axe-devtools-web-accessib/lhdoppojpmngadmnindnejefpokejbdd)\n2.
Go into a service overview and run the scanner from axe devtools\n3. You
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BACKPORT-->

Co-authored-by: Sergi Romeu <sergi.romeu@elastic.co>

x-pack/solutions/observability/plugins/apm/public/components/shared/charts/latency_chart/latency_aggregation_type_select.tsx

@@ -27,6 +27,9 @@ export function LatencyAggregationTypeSelect({
     <EuiSelect
       data-test-subj="apmLatencyChartSelect"
       compressed
+      aria-label={i18n.translate('xpack.apm.serviceOverview.latencyChartTitle.selector', {
+        defaultMessage: 'Metric selector',
+      })}
       prepend={i18n.translate('xpack.apm.serviceOverview.latencyChartTitle.prepend', {
         defaultMessage: 'Metric',
       })}