Remove indentation from the request payload JSON

[shibayan]

Believe it or not, some ACME implementations return an error if there is indentation in the JSON of the request payload.
win-acme/win-acme#1565

I noticed this problem in the ACME implementation of ZeroSSL.

[ebekker]

Hmm, interesting. I assume you confirmed with this change, it is now working with ZeroSSL or similar implementations?

[shibayan]

Yes, removing the indentation worked correctly. It's very strange.

I am working on the EAB support now and the following code confirms that it works. Although not included in the PR, ACMESharpCore directly incorporates the version with the indentation removed.
polymind-inc/acmebot#252

Error message:

ProblemType":14,"ProblemTypeRaw":"urn:ietf:params:acme:error:malformed","ProblemDetail":"The JWS Protected Header MUST be present","ProblemStatus":400,