feat: add settings for go sql.DB settings

[reimda]

resolves #11498

The golang SQL API exposes a few settings related to pooled connections. (see https://pkg.go.dev/database/sql#DB) These settings need to be changed for some SQL drivers to connect reliably to some databases.

This PR adds telegraf settings that mirror the golang sql settings. This allows users to set them through telegraf.conf and be able to connect to databases that require specific settings.

The golang sql settings have defaults and since telegraf didn't set the settings, it was using the defaults. I mirrored the default values in the new telegraf settings. This should make the sql output behave the same as before.

[srebhan]

Thanks @reimda for the fix. I only have a comment about option naming to make it consistent with the sql input plugin...

[powersj]

Thanks for jumping on this one!

[telegraf-tiger]

Download PR build artifacts for linux_amd64.tar.gz, darwin_amd64.tar.gz, and windows_amd64.zip.
Downloads for additional architectures and packages are available below.

☺️ This pull request doesn't significantly change the Telegraf binary size (less than 1%)

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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_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

[srebhan]

Thanks @reimda! Looks good to me.