Add invoke --data-file option and e2e tests

[wcs1only]

Description

The dapr invoke command now also has a data-file option.

Issue reference

We strive to have all PR being opened based on an issue, where the problem or feature have been discussed prior to implementation.

Please reference the issue this PR will close: #668

Checklist

Please make sure you've completed the relevant tasks for this PR, out of the following list:

• Code compiles correctly
• Created/updated tests
• Extended the documentation

[codecov]

Codecov Report

Merging #680 (ac09016) into master (494c24b) will decrease coverage by 0.17%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #680      +/-   ##
==========================================
- Coverage   19.97%   19.79%   -0.18%     
==========================================
  Files          28       28              
  Lines        1367     1364       -3     
==========================================
- Hits          273      270       -3     
  Misses       1061     1061              
  Partials       33       33              

Impacted Files	Coverage Δ
pkg/standalone/client.go	0.00% <ø> (ø)
pkg/standalone/invoke.go	72.72% <100.00%> (-3.28%)	⬇️

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