deps: replace serde-hex with custom serialize

[jxs]

closes #44

[divagant-martian]

This does not achieve the desired output.

Current way has a 0x prefix, and this change removes the prefix.

What's the motivation for this change?

[divagant-martian]

Just saw #44 , could you link to the relevant issues next time to understand the context?

That being said, all in favor for removing a dep that's there just for this, but the output should remain the same. We could just create the module that does the prefix prepending and stripping and relies on hex underneath

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extra context: https://github.com/sigp/enr/pull/38

[jxs]

created https://github.com/sigp/enr/pull/49 to address the clippy lints

[divagant-martian]

@jxs can you merge master to get this one in?

[jxs]

@jxs can you merge master to get this one in?

yup, done! :)