[Migrate CI] Added workflow for GitHub actions CI. Deleted travis.yml.

[anvithks]

What type of PR is this?
/kind enhancement

What this PR does / why we need it:
This PR adds the Github Actions workflow to migrate the CI.

Which issue(s) this PR fixes:
Fixes #27

Test Report Added?:
/kind TESTED

Test Report:
The Workflow run can be seen in the Actions Tab.
Special notes for your reviewer:

[codecov]

Codecov Report

Merging #28 (834e5f6) into master (2e0cb71) will decrease coverage by 2.28%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master      #28      +/-   ##
==========================================
- Coverage   41.40%   39.12%   -2.29%     
==========================================
  Files          33       33              
  Lines        5598     4989     -609     
==========================================
- Hits         2318     1952     -366     
+ Misses       2819     2578     -241     
+ Partials      461      459       -2     

Impacted Files	Coverage Δ
client/volume.go	62.31% <0.00%> (-8.40%)	⬇️
pkg/driverconfig/config.go	25.00% <0.00%> (-8.34%)	⬇️
client/fileshare.go	65.95% <0.00%> (-7.22%)	⬇️
client/dock.go	42.85% <0.00%> (-7.15%)	⬇️
client/pool.go	42.85% <0.00%> (-7.15%)	⬇️
client/host.go	61.11% <0.00%> (-6.98%)	⬇️
client/version.go	46.15% <0.00%> (-6.79%)	⬇️
client/profile.go	55.55% <0.00%> (-6.42%)	⬇️
pkg/controller/fileshare/filesharecontroller.go	20.23% <0.00%> (-4.77%)	⬇️
pkg/controller/volume/volumecontroller.go	12.90% <0.00%> (-3.63%)	⬇️
... and 22 more

[skdwriting]

LGTM

[rajat-soda]

LGTM

[skdwriting]

CI migration in progerss to github actions, local ci ok. hence merging.