feat(processors.parser): Allow also non-string fields

[srebhan]

• Updated associated README.md.
• Wrote appropriate unit tests.
• Pull request title or commits are in conventional commit format

resolves #13546

This PR allows to parse non-string fields in the parser processor to e.g. decode binary data. In the example from #13546 the input data looks like

mes,t1=y operating_state=13u,value=42.0 1688556620000000000

and the operating_state should be decoded into its bit-values. With the present PR this can easily be done using

[[processors.parser]]
  parse_fields = ["operating_state"]
  drop_original = false
  merge = "override"
  data_format = "binary"

  [[processors.parser.binary]]
    entries = [
      { name = "alarm_0", type = "bool", bits=1 },
      { name = "alarm_1", type = "bool", bits=1 },
      { name = "alarm_2", type = "bool", bits=1 },
      { name = "alarm_3", type = "bool", bits=1 },
      { name = "alarm_4", type = "bool", bits=1 },
      { name = "alarm_5", type = "bool", bits=1 },
      { name = "alarm_6", type = "bool", bits=1 },
      { name = "alarm_7", type = "bool", bits=1 },
    ]

resulting in the following output

mes,t1=y alarm_0=false,alarm_1=false,alarm_2=false,alarm_3=false,alarm_4=true,alarm_5=true,alarm_6=false,alarm_7=true,operating_state=13i,value=42 1688556620000000000

[telegraf-tiger]

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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_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]

@srebhan assigning to you as well while you wait on feedback