Prevent dev dependencies from breaking tests and examples

[Ogeon]

Make it so examples build and CI can run with a couple of temporary fixes.

• Pins ron, since they bumped the MSRV in 0.8.1.
• Enables the srd feature for clap, since it's required in 3.2.25.

Fixes #348

[Ogeon]

bors r+

[bors[bot]]

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• ci