regexes with curlies stopped to work

[ignaqui]

I'm submitting a ...

• Bug report
• Feature requestdd
• Question / Support request

If you don't send bug report, remove sections below

For bug report please include this information:

Software Versions

Grafana	Zabbix	Grafana-Zabbix Plugin
4.4.1	3.2.4	3.5.1

What did you do?

Once I updated grafana and grafana-zabbix, variables in templates stopped to work.
It appeared that dot separator has been phased out from data source in favor of curlies.
However, I think this broke my regexes which have curlies inside.

What was the expected result?

The following query used to return proper values:
/alu/./tw-(nyc|que|brx|dwt|brk)-sta_(\w|\d)*-alu-[0-9{2}/

What happened instead?

This query does not work:
{alu}{/tw-(nyc|que|brx|dwt|brk)-sta_(\w|\d)*-alu-[0-9]{2}/}

and this does work:
{alu}{/tw-(nyc|que|brx|dwt|brk)-sta_(\w|\d)*-alu-[0-9]*/}

I tried to mask curlies with backslash and use double curlies without success

[alexanderzobnin]

@ignaqui this is a great test case! I'll add it to unit tests to ensure things are working in next releases.