Use commas instead of blanks as separators for multi-valued properties

Description

People usually expect commas to be used as value separators in properties, including frameworks that integrate with Hibernate Search (Quarkus).

We should probably use it for the "hosts" property in the Elasticsearch backend, and maybe all other multi-valued properties.

Commas are relatively unlikely to show up in host definitions anyway, and I suspect we could simply URL-encode the commas if necessary. Let's add a test for that.

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Status

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Reporter

Yoann Rodière

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Priority

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