[Backport 2.x] [Refactor] Strings methods other than MediaType

[opensearch-trigger-bot]

Backport 1d28fac from #9126.

[opensearch-trigger-bot]

Compatibility status:

> Task :checkCompatibility
Incompatible components: [https://github.com/opensearch-project/alerting.git, https://github.com/opensearch-project/index-management.git, https://github.com/opensearch-project/anomaly-detection.git, https://github.com/opensearch-project/geospatial.git, https://github.com/opensearch-project/cross-cluster-replication.git, https://github.com/opensearch-project/notifications.git, https://github.com/opensearch-project/ml-commons.git]
Components skipped due to git failures: [https://github.com/opensearch-project/opensearch-oci-object-storage.git]
Compatible components: [https://github.com/opensearch-project/security.git, https://github.com/opensearch-project/asynchronous-search.git, https://github.com/opensearch-project/job-scheduler.git, https://github.com/opensearch-project/common-utils.git, https://github.com/opensearch-project/sql.git, https://github.com/opensearch-project/reporting.git, https://github.com/opensearch-project/observability.git, https://github.com/opensearch-project/k-nn.git, https://github.com/opensearch-project/neural-search.git, https://github.com/opensearch-project/performance-analyzer.git, https://github.com/opensearch-project/security-analytics.git, https://github.com/opensearch-project/performance-analyzer-rca.git]

BUILD SUCCESSFUL in 25m 4s

[github-actions]

Gradle Check (Jenkins) Run Completed with:

• RESULT: FAILURE ❌
• URL: https://build.ci.opensearch.org/job/gradle-check/21927/
• CommitID: 9856e55
  Please examine the workflow log, locate, and copy-paste the failure(s) below, then iterate to green.
  Is the failure a flaky test unrelated to your change?

[github-actions]

Gradle Check (Jenkins) Run Completed with:

• RESULT: SUCCESS ✅
• URL: https://build.ci.opensearch.org/job/gradle-check/21938/
• CommitID: 9856e55

[codecov]

Codecov Report

Merging #9128 (9856e55) into 2.x (e59b21a) will decrease coverage by 0.09%.
The diff coverage is 67.60%.

@@             Coverage Diff              @@
##                2.x    #9128      +/-   ##
============================================
- Coverage     70.81%   70.73%   -0.09%     
+ Complexity    57425    57420       -5     
============================================
  Files          4754     4754              
  Lines        271688   271687       -1     
  Branches      40070    40070              
============================================
- Hits         192408   192184     -224     
- Misses        62717    63047     +330     
+ Partials      16563    16456     -107     

Files Changed	Coverage Δ
...luster/snapshots/create/CreateSnapshotRequest.java	71.51% <ø> (+1.21%)	⬆️
...cluster/metadata/MetadataIndexTemplateService.java	81.80% <0.00%> (-1.13%)	⬇️
...r/src/main/java/org/opensearch/common/Strings.java	66.66% <ø> (-4.77%)	⬇️
...pensearch/common/settings/PropertyPlaceholder.java	92.45% <ø> (ø)
...apshots/blobstore/BlobStoreIndexShardSnapshot.java	73.57% <ø> (+1.03%)	⬆️
...ch/repositories/blobstore/BlobStoreRepository.java	59.65% <ø> (+0.06%)	⬆️
...ava/org/opensearch/snapshots/SnapshotsService.java	40.15% <33.33%> (+0.22%)	⬆️
.../main/java/org/opensearch/core/common/Strings.java	66.32% <68.75%> (+1.75%)	⬆️
...h/cluster/metadata/MetadataCreateIndexService.java	78.57% <100.00%> (-0.18%)	⬇️
...g/opensearch/repositories/RepositoriesService.java	72.57% <100.00%> (+0.33%)	⬆️

... and 468 files with indirect coverage changes