[REQ][typescript-axios] useSingleRequestParameter should mark parameter optional if all properties are optional

Created by: codeserk

This PR uses a default value to requestParameters (= {}) if all the parameters are optional.

fixes #6440 (closed)

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@benwiley4000 I think this is not exactly the solution you had in mind, but it should work alike: If all the parameters are optional, you can use it without parameters (myApiCall()). Using default parameter instead of making it optional makes it a bit less complex.

@TiFu @taxpon @sebastianhaas @kenisteward @Vrolijkx @macjohnny @nicokoenig @topce @akehir @petejohansonxo @amakhrov