Fix flakiness in runIndexCleanerTest by filtering Jaeger indices (#7004)

RESOLVE #7002
**issue:** - The test `runIndexCleanerTest` was flaky because it
included unrelated system indices (e.g.,
`top_queries-2025.04.08-51429`).

## Description of the changes
- Added `strings` import to use `strings.HasPrefix`.
- Filtered indices to only include those starting with
`prefixWithSeparator + "jaeger-"`.
- Updated the assertion to use `filteredIndices` instead of raw
`indices`.

**Impact:** Ensures the test only checks relevant Jaeger indices,
improving reliability.

## Checklist
- [✓]I have read
https://github.com/jaegertracing/jaeger/blob/master/CONTRIBUTING_GUIDELINES.md
- [✓] I have signed all commits
- [  ] I have added unit tests for the new functionality
- [✓]I have run lint and test steps successfully
  - for `jaeger`: `make lint test`
  - for `jaeger-ui`: `npm run lint` and `npm run test`

---------

Signed-off-by: Shubham Solanki <[email protected]>
Signed-off-by: Yuri Shkuro <[email protected]>
Co-authored-by: Yuri Shkuro <[email protected]>

Author: 0xShubhamSolanki

internal/storage/integration/es_index_cleaner_test.go

@@ -8,6 +8,7 @@ import (
 	"fmt"
 	"net/http"
 	"os/exec"
+	"strings"
 	"testing"
 
 	elasticsearch8 "github.com/elastic/go-elasticsearch/v8"
@@ -154,16 +155,23 @@ func runIndexCleanerTest(t *testing.T, client *elastic.Client, v8Client *elastic
 	require.NoError(t, err)
 	err = runEsCleaner(0, envVars)
 	require.NoError(t, err)
-	indices, err := client.IndexNames()
+	foundIndices, err := client.IndexNames()
 	require.NoError(t, err)
 	if prefix != "" {
 		prefix += "-"
 	}
+	var actual []string
+	for _, index := range foundIndices {
+		// ignore system indices https://github.com/jaegertracing/jaeger/issues/7002
+		if strings.HasPrefix(index, prefix+"jaeger") {
+			actual = append(actual, index)
+		}
+	}
 	var expected []string
 	for _, index := range expectedIndices {
 		expected = append(expected, prefix+index)
 	}
-	assert.ElementsMatch(t, indices, expected, "indices found: %v, expected: %v", indices, expected)
+	assert.ElementsMatch(t, actual, expected, "indices found: %v, expected: %v", foundIndices, expected)
 }
 
 func createAllIndices(client *elastic.Client, prefix string, adaptiveSampling bool) error {