docs: update parse server version reqs

[cbaker6]

New Pull Request Checklist

• I am not disclosing a vulnerability.
• I am creating this PR in reference to an issue.

Issue Description

Some places in the docs mention Parse Server > 4.5.0 which really means 5.0.0+

Related issue: #n/a

Approach

Change all relevant references to 5.0.0+

TODOs before merging

• Add changes to documentation (guides, repository pages, in-code descriptions)

[parse-github-assistant]

Thanks for opening this pull request!

• 🎉 We are excited about your hands-on contribution!

[codecov]

Codecov Report

Merging #279 (b6be046) into main (6ef226b) will increase coverage by 0.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main     #279      +/-   ##
==========================================
+ Coverage   82.22%   82.23%   +0.01%     
==========================================
  Files         104      104              
  Lines       10574    10574              
==========================================
+ Hits         8694     8696       +2     
+ Misses       1880     1878       -2     

Impacted Files	Coverage Δ
Sources/ParseSwift/API/API.swift	97.18% <ø> (ø)
Sources/ParseSwift/Types/Query.swift	93.60% <ø> (ø)
Sources/ParseSwift/Objects/ParseUser.swift	79.93% <0.00%> (+0.21%)	⬆️

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