[typescript] Default auth method support and optional param object when all params optional

[davidgamero]

Add an optional default?: SecurityAuthentication field to the AuthMethodsConfiguration type that populates a similarly typed optional field on the AuthMethods type.
This enables passing a custom object satisfying the SecurityAuthentication interface for authentication purposes in the config either when a client is created or overriding at api call time via config param.

Also carry over optional singleParameter when all params optional from here

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

[davidgamero]

I'm happy to split this into two separate PR's if this is too messy btw

[TiFu]

Thank you for the pull request! :)
I think we can keep it as 1 PR - it's not messy at all and quite easy to read & understand.

Added a couple comments with questions and a small change.

[davidgamero]

i've moved the default auth option to the config param instead to keep the override functinality

[davidgamero]

ive excluded the inversify portion since the injection was essentially a whole separate feature

[OliverMKing]

Really looking forward to this change 😄.

[TiFu]

LGTM! Many thanks for the PR! :)