docs: Add example output section to HTTP plugin

[sspaink]

This pull request:

• Adds a example output section to the http plugin readme to resolve linter error I noticed here: https://github.com/influxdata/telegraf/runs/7306583417?check_suite_focus=true, this failing in an unrelated PR is probably something that needs to be fixed in the github action but I didn't address this.
• Make the linter more lenient and doesn't mark links against the long line rule, it looks like the logic is simpler now using the actual string to get the length as well. Still seems accurate when testing it locally.

[powersj]

Hmm ignoring the URL text means that reading these in a text editor doesn't actually make the line length 80 characters anymore. And the user will have random lines that shoot out.

[sspaink]

True, but I was thinking maybe links could be the exception? In this case the link even on its own line exceed the 80 character limit. My main motivation is just to get the green check mark, so I could perhaps just shorten the URL (this seems legit?) or not include it? Although the example output seems a bit random without the context of the article.

[powersj]

My main motivation is just to get the green check mark, so I could perhaps just shorten the URL (this seems legit?) or not include it?

Have you seen the reference-style link method? I wasn't aware of this till Dave went through updating the other READMEs
https://www.markdownguide.org/basic-syntax/#reference-style-links

This example output was taken from [this instructional article][1].

[1]: https://docs.influxdata.com/telegraf/v1.21/guides/using_http/

[sspaink]

I didn't know you could do that! Seems like a good solution to me, I've updated the PR accordingly.

[telegraf-tiger]

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DEB	RPM	TAR GZ	ZIP
amd64.deb	aarch64.rpm	darwin_amd64.tar.gz	windows_amd64.zip
arm64.deb	armel.rpm	darwin_arm64.tar.gz	windows_i386.zip
armel.deb	armv6hl.rpm	freebsd_amd64.tar.gz
armhf.deb	i386.rpm	freebsd_armv7.tar.gz
i386.deb	ppc64le.rpm	freebsd_i386.tar.gz
mips.deb	riscv64.rpm	linux_amd64.tar.gz
mipsel.deb	s390x.rpm	linux_arm64.tar.gz
ppc64el.deb	x86_64.rpm	linux_armel.tar.gz
riscv64.deb		linux_armhf.tar.gz
s390x.deb		linux_i386.tar.gz
		linux_mips.tar.gz
		linux_mipsel.tar.gz
		linux_ppc64le.tar.gz
		linux_riscv64.tar.gz
		linux_s390x.tar.gz
		static_linux_amd64.tar.gz