feat(processors.aws_ec2): Allow to use instance metadata

[srebhan]

Summary

Allow to use instance metadata to annotate metrics according to https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ec2-instance-metadata.html.

Checklist

• No AI generated code was used in this PR

Related issues

resolves #15789

[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

[kirillmandrygin]

Hi @srebhan ! It is working good but I have two issues:

1. Error when I run telegraf with --test:

[signal SIGSEGV: segmentation violation code=0x1 addr=0x0 pc=0x740411b]

goroutine 109 [running]:
github.com/influxdata/telegraf/plugins/processors/aws_ec2.(*AwsEc2Processor).Stop(0xc00252e9c0?)
	/go/src/github.com/influxdata/telegraf/plugins/processors/aws_ec2/ec2.go:166 +0x3b
github.com/influxdata/telegraf/models.(*RunningProcessor).Stop(...)
	/go/src/github.com/influxdata/telegraf/models/running_processor.go:115
github.com/influxdata/telegraf/agent.(*Agent).runProcessors.func1(0xc001fec0c0)
	/go/src/github.com/influxdata/telegraf/agent/agent.go:666 +0x172
created by github.com/influxdata/telegraf/agent.(*Agent).runProcessors in goroutine 14
	/go/src/github.com/influxdata/telegraf/agent/agent.go:656 +0x3e

2. Metadata tag added with slash (for example: test_metric{/Name="test-instance"}), is this expected behaviour?

[srebhan]

@kirillmandrygin can you please open an issue with the information of your previous post and assign it to me or let me know the issue number!?!

[kirillmandrygin]

@srebhan #15906