feat(processors.parser): Add base64 decode for fields

[mstrandboge]

Summary

Adds a base64 decode option for any field specified in the parse_fields config option.

Checklist

• [X] No AI generated code was used in this PR

Related issues

resolves #15130

[mstrandboge]

@RodrigoDornelles are you able to test if this works as you expect? Thanks!

[RodrigoDornelles]

I am currently homeless, no longer have my computer.

😕

[powersj]

I am currently homeless, no longer have my computer.

😕

Really sorry to hear about this :( I hope you are ok and are able to get re-established.

[telegraf-tiger[bot]]

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.

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

:package: 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

[srebhan]

@powersj could you please take another look after the code change!?