fix(outputs.influxdb_v3): Remove duplicate timeout setting

[WZH8898]

Summary

Fix TOML tag collision in outputs.influxdb_v3 configuration.

The clientConfig struct defines a Timeout field with toml:"timeout", while the embedded HTTPClientConfig also defines the same TOML tag. This causes the TOML parser to detect multiple fields matching timeout and refuse to set the value.

This change removes the duplicated Timeout field and relies on the embedded HTTPClientConfig.Timeout, which already provides the same functionality.

Checklist

• No AI generated code was used in this PR

Related Issues

resolves #18502

[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 @WZH8898!

Please keep the PR template next time as a fixed pattern allows us to get an overview easier (e.g. keep resolves instead of changing it to Fixes or removing the second AI choice).

[skartikey]

@WZH8898 Thanks for the contribution!