[Refactor] Strings utility methods to core library

[heemin32]

Description

[Refactor] Strings utility methods to core library

Issues Resolved

N/A

Check List

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[codecov]

Codecov Report

Merging #379 (2e04baf) into main (d509bfc) will decrease coverage by 0.15%.
The diff coverage is n/a.

@@             Coverage Diff              @@
##               main     #379      +/-   ##
============================================
- Coverage     88.71%   88.56%   -0.15%     
+ Complexity      754      752       -2     
============================================
  Files            92       92              
  Lines          2711     2711              
  Branches        220      220              
============================================
- Hits           2405     2401       -4     
- Misses          228      230       +2     
- Partials         78       80       +2     

Files Changed	Coverage Δ
...patial/ip2geo/action/RestGetDatasourceHandler.java	100.00% <ø> (ø)
...h/geospatial/ip2geo/common/ParameterValidator.java	90.00% <ø> (ø)

... and 2 files with indirect coverage changes

[martin-gaievski]

We don't need Strings class, unless it's used somewhere else in our plugin we need to remove this import

[heemin32]

It is used in this class.

[opensearch-trigger-bot]

The backport to 2.x failed:

The process '/usr/bin/git' failed with exit code 1

To backport manually, run these commands in your terminal:

# Fetch latest updates from GitHub
git fetch
# Create a new working tree
git worktree add .worktrees/backport-2.x 2.x
# Navigate to the new working tree
cd .worktrees/backport-2.x
# Create a new branch
git switch --create backport/backport-379-to-2.x
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 df00d455e393fec6c3106918903d2e27efb7bf90
# Push it to GitHub
git push --set-upstream origin backport/backport-379-to-2.x
# Go back to the original working tree
cd ../..
# Delete the working tree
git worktree remove .worktrees/backport-2.x

Then, create a pull request where the base branch is 2.x and the compare/head branch is backport/backport-379-to-2.x.