missing support for xsd:float

[laurianvm]

A recent run of the linked-data-etl workflow in observatory-bpns-crate reported errors in semantify:
Workflow run details.

The error states that xsd:float is not supported.

(### FYI:

• This issue was reported in emo-bon/observatory-bpns-crate.
• xsd:float is the expected datatype, as indicated in the logsheet schema.
• Currently, xsd:float → xsd:double in the templates (sediment_measured.ldt.ttl & water_measured.ldt.ttl)

[mpo-vliz]

just checked xsd:float does exist -- see https://www.w3.org/2001/XMLSchema#float -- and is distinct from https://www.w3.org/2001/XMLSchema#double

thing is however that the float in python is already double precision -- so we should be able to cover this by exactly doing the same thing and just slashing ^^xsd:float at the end

which begs the question: do we really need to make a distinction that is not (no longer?) actually there, or even worse artificially produce some historic single precision?