fix(inputs.temp): Fix regression in metric formats

[srebhan]

Summary

PR #14575 introduces a regression for the default v2 metric format. Additionally, a subtle difference for alarm data was discovered in v1 metrics. This has gone unnoticed due to incorrect test-data.

This PR adds a unit-test for the test-data using the reference implementations of previous versions that are known-good in producing v1 and v2 metrics. The PR furthermore, corrects the test-data and fixes the introduced regressions in both v1 and v2 metric format.

Checklist

• No AI generated code was used in this PR

Related issues

resolves #14646

[telegraf-tiger]

Download PR build artifacts for linux_amd64.tar.gz, darwin_arm64.tar.gz, and windows_amd64.zip.
Downloads for additional architectures and packages are available below.

👍 This pull request doesn't change the Telegraf binary size

📦 Click here to get additional PR build artifacts

Artifact URLs

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

[Xyaren]

It would be nice if the release of this fix can be expedited.