test(linters): Enable testifylint: blank-import, float-compare, negative-positive, nil-compare and useless-assert

[zak-pawel]

Summary

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• No AI generated code was used in this PR

Related issues

resolves #15533
resolves #15534
resolves #15536
resolves #15537
resolves #15538

[srebhan]

Thanks @zak-pawel for going through all those files! Two comments from my side and a request to define the delta 0.001 as a constant in the testutil package so we can reduce the delta if required...

[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_arm64.zip
armel.deb	armv6hl.rpm	freebsd_amd64.tar.gz	windows_i386.zip
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

[srebhan]

Thanks @zak-pawel!