feat(inputs.tail): Allow handling of quoted strings spanning multiple lines

[srebhan]

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

This PR allows to handle files with quoted strings spanning multiple lines, e.g.

1660819827425,12,Get Homepage264 /api/version,200,OK,DR 4-4,text,true,,896,787,6,16,https://abc.test.com/api/version,12,0,0,SP-1

1660819827419,17,LoginB3 PLANs /auth/callback,500,Internal Server Error,StoreReplenishment 3-1,text,false,"Test failed: code expected to equal /

****** received  : [[[5]]]00

****** comparison: [[[2]]]00

/",344,980,2,16,https://abc.test.com/,17,0,0,SP-1

1660819827046,391,Submit Login,,"Number of samples in transaction : 4, number of failing samples : 1",Store 3-1,,false,,4838,7608,2,16,null,388,2,0,SP-1
1660819826877,558,Do Login Support,,"Number of samples in transaction : 8, number of failing samples : 1",Store 3-1,,false,,12068,10167,2,16,null,440,4,50,SP-1
1660819827419,26,Get Homepage278 /api/session,200,OK,DR 4-2,text,true,,2267,893,6,16,https://abc.test.com/api/session,26,0,0,SP-1
1660819827445,15,Get Homepage273 /api/scenarios,200,OK,DR 4-2,text,true,,888,803,6,16,https://abc.test.com/api/scenarios,15,0,0,SP-1
1660819827349,115,Get Homepage261 /api/reports,200,OK,SF 1-1,text,true,,36552,797,1,16,https://abc.test.com/api/reports,115,0,0,SP-1

(taken from Slack).

The feature is disabled by default and has to be enabled using a new quotation option for inputs.tail.multiline.

[powersj]

@srebhan I know we chatted about this one in standup, what did we decide as far as the way forward?

[srebhan]

@powersj we agreed on specifying the quotation quotes explicitly, which is done by the last update. :-)

[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
		static_linux_amd64.tar.gz

[powersj]

Thanks for the additional error condition tests!