Add map as another reference type to check to show warnings

[mrodm]

What does this PR do?

This PR updates validation rule that shows warnings in case of reference types to include "map" as another element to be taken into account according to #316 (comment).

Follow up of this PR #389

Checklist

- [ ] I have added test packages to test/packages that prove my change is effective.

• I have added an entry in spec/changelog.yml.

Related issues

• Relates Warning when dashboard with visualisations by reference instead of value exist #316

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• Start Time: 2022-09-13T10:05:57.094+0000

• Duration: 7 min 57 sec

Test stats 🧪

Test	Results
Failed	0
Passed	622
Skipped	0
Total	622

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🌐 Coverage report

Name	Metrics % (covered/total)	Diff
Packages	100.0% (7/7)	💚
Files	70.833% (17/24)	👍
Classes	78.788% (26/33)	👍
Methods	58.824% (60/102)	👍
Lines	44.592% (536/1202)	👎 -0.037
Conditionals	100.0% (0/0)	💚