Rename getPresences to getUsers

[chacha912]

What this PR does / why we need it?

Rename doc.getPresences() to doc.getUsers() as the returned value aligns more closely with user information, making this name easier to comprehend.

The reason users is used in getUsers is that using clients (as yorkie Client) might imply that it should hold all information about the yorkie client. However, users only contain clientID and presence information, so I used the term users instead of clients.

Any background context you want to provide?

What are the relevant tickets?

Related yorkie-team/yorkie#609, yorkie-team/yorkie#665

Checklist

• Added relevant tests or not required
• Didn't break anything

[codecov]

Codecov Report

Merging #618 (cfbd698) into main (2ac69bb) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##             main     yorkie-team/yorkie-js-sdk#618   +/-   ##
=======================================
  Coverage   88.62%   88.62%           
=======================================
  Files          80       80           
  Lines        8893     8893           
  Branches      817      817           
=======================================
  Hits         7881     7881           
  Misses        704      704           
  Partials      308      308           

Files Changed	Coverage Δ
src/client/client.ts	76.81% <ø> (ø)
src/document/document.ts	76.27% <100.00%> (ø)
test/integration/presence_test.ts	100.00% <100.00%> (ø)

[hackerwins]

I will close this PR for now. Please let me know when you proceed.