fix(inputs.http_listener_v2): Wrap timestamp parsing error messages

[powersj]

Summary

When a timestamp fails to parse it produces a very vauge message:

2024-04-26T12:45:22Z E! [inputs.file] Error in plugin: could not parse "data": invalid number

This does not tell you what the data is, or even that it is the timestamp that failed to parse. Instead this PR changes to this:

2024-04-26T12:47:34Z E! [inputs.file] Error in plugin: could not parse "data": unable to parse timestamp "12a34567890": invalid number

Checklist

• No AI generated code was used in this PR

Related issues

fixes: #15237

[telegraf-tiger]

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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