fix(inputs.mysql): Parse boolean values in metric v1 correctly

[srebhan]

Summary

The current code for metric version 1 parses everything as an integer for global status queries. This leads to zero values for boolean values such as "ON" or "true" which are in turn perceived as "wrong" on the database side.

This PR fixes parsing of boolean values and emits a (single-time) warning for other values which might contain strings, floats etc resulting in zero values. The PR does not change the behavior for those other values to prevent changes of field-types for the metric output.

Checklist

• No AI generated code was used in this PR

Related issues

resolves #6417

[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

[powersj]

Thanks! So it looks like the user always got 0 back, and this effectively unbreaks them by allowing for a 1 when it is on or true.