Fix: Icon purpose doesn't support combination of values

[sarvaje]

Fix #3791

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For non-trivial changes, please make sure you also:

• Added/Updated related documentation.
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Short description of the change(s)

Allow to the icons in manifest to have a combination of values.

[jsf-clabot]

Thank you for your submission, we really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.

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Jesus David Garcia Gomez seems not to be a GitHub user. You need a GitHub account to be able to sign the CLA. If you have already a GitHub account, please add the email address used for this commit to your account.

[jsf-clabot]

Thank you for your submission, we really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.

---

Jesus David Garcia Gomez seems not to be a GitHub user. You need a GitHub account to be able to sign the CLA. If you have already a GitHub account, please add the email address used for this commit to your account.

[sarvaje]

@webhintio/contributors anyone knows how to update the CLA, I didn't realize the email configured was wrong :s

[molant]

@sa change the author in the commit and reopen the pr?