Modify script to accept inclusion and exclustion filters as variables

[kavirajk]

What this PR does / why we need it:
Support gcplog terraform script to accept inclusion and exclusion filter as variables.

Which issue(s) this PR fixes:
Fixes #
NA

Special notes for your reviewer:

Checklist

• Documentation added
• Tests updated

[codecov-io]

Codecov Report

Merging #3422 (28a25c6) into master (20ef66d) will decrease coverage by 0.05%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #3422      +/-   ##
==========================================
- Coverage   63.01%   62.95%   -0.06%     
==========================================
  Files         205      205              
  Lines       17499    17499              
==========================================
- Hits        11027    11017      -10     
- Misses       5481     5494      +13     
+ Partials      991      988       -3     

Impacted Files	Coverage Δ
pkg/promtail/positions/positions.go	46.80% <0.00%> (-11.71%)	⬇️
pkg/querier/queryrange/limits.go	86.91% <0.00%> (-1.87%)	⬇️
pkg/ingester/checkpoint.go	72.83% <0.00%> (-1.14%)	⬇️
pkg/promtail/targets/file/tailer.go	78.57% <0.00%> (+5.35%)	⬆️