docs: explain quantity data type for analysis targets

[StackScribe]

Summary

Explains the use of Kubernetes quantity type rather than float for values specified for values in the target specification.

Fixes #2610

Checks

• My PR fulfills the Definition of Done of the corresponding issue and not more (or parts if the issue is separated
  into multiple PRs)
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  see Contribution Guide)
• My PR title is formatted according to the semantic PR conventions described in
  the Contribution Guide
• My content follows the style guidelines of this project (YAMLLint, markdown-lint)
• [ n/a] I regenerated the auto-generated docs for Helm and the CRD documentation (if applicable)
• I have performed a self-review of my content including grammar and typo errors and also checked the rendered page
  from the Netlify deploy preview
• My changes result in all-green PR checks (first-time contributors need to ask a maintainer to approve their test runs)

[netlify]

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[sonarqubecloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

No Coverage information
No Duplication information

[odubajDT]

In general, didn't we agree on updating the docs-new folder from now on? @mowies @StackScribe

[mowies]

yes @odubajDT . new content should be added to the docs-new folder

[mowies]

LGTM, but please move the changes to the docs-new folder :)

[sonarqubecloud]

Quality Gate passed

Kudos, no new issues were introduced!

0 New issues
0 Security Hotspots
No data about Coverage
No data about Duplication

See analysis details on SonarCloud

[codecov]

Codecov Report

Merging #2615 (ee95ab6) into main (601a053) will decrease coverage by 0.11%.
Report is 10 commits behind head on main.
The diff coverage is n/a.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2615      +/-   ##
==========================================
- Coverage   85.59%   85.48%   -0.11%     
==========================================
  Files         155      155              
  Lines       10175    10175              
==========================================
- Hits         8709     8698      -11     
- Misses       1190     1198       +8     
- Partials      276      279       +3     

see 3 files with indirect coverage changes

Flag	Coverage Δ
certificate-operator	67.43% <ø> (ø)
component-tests	56.36% <ø> (-0.77%)	⬇️
lifecycle-operator	84.44% <ø> (ø)
metrics-operator	87.43% <ø> (ø)
scheduler	36.53% <ø> (ø)

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