* fix: allow URIs without double slash in Resource and ResourceTemplate (RFC 3986)
The URI regex required "://" after the scheme, rejecting valid URIs
like urn:isbn:123, mailto:user@example.com, config:key, and data:
URIs. RFC 3986 only requires ":" after the scheme; the "//" is part
of the authority component which is optional.
Changed both Resource.URI_PATTERN and ResourceTemplate.URI_TEMPLATE_PATTERN
to require ":" instead of "://".
Adds data-provider tests for URIs without double slash in both classes.
Fixes#293
* Reword unit tests
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Co-authored-by: Christopher Hertel <mail@christopher-hertel.de>
