Improve Grafana notification tags

[PetrSladek]

Added the ability to set global tags for Grafana annotation and the ability to set tags per Notification with templating capability

[codecov]

Codecov Report

❌ Patch coverage is 81.25000% with 6 lines in your changes missing coverage. Please review.
✅ Project coverage is 55.60%. Comparing base (f485671) to head (c490180).
⚠️ Report is 17 commits behind head on master.

Files with missing lines	Patch %	Lines
pkg/services/grafana.go	79.31%	4 Missing and 2 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #394      +/-   ##
==========================================
+ Coverage   55.35%   55.60%   +0.25%     
==========================================
  Files          35       46      +11     
  Lines        3438     4156     +718     
==========================================
+ Hits         1903     2311     +408     
- Misses       1256     1515     +259     
- Partials      279      330      +51     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[pasha-codefresh]

Hey @PetrSladek , could you please resolve conflicts and DCO check