Fix bytes returned from hex fingerprint -o tsv

[devigned]

The hex fingerprint of a Key Vault certificate returns as bytes in py3. This corrects that and returns a str as the method says it should.

$ az keyvault certificate show --vault-name testvaultdj -n testcert --query "x509ThumbprintHex" -o tsv
b'73863FFDAD3BA0E7C08BAEFBAD09F661298341C6'

After the fix

$ az keyvault certificate show --vault-name testvaultdj -n testcert --query "x509ThumbprintHex" -o tsv
73863FFDAD3BA0E7C08BAEFBAD09F661298341C6

[codecov-io]

Codecov Report

Merging #3053 into master will decrease coverage by <.01%.
The diff coverage is 50%.

@@            Coverage Diff             @@
##           master    #3053      +/-   ##
==========================================
- Coverage   63.15%   63.15%   -0.01%     
==========================================
  Files         484      484              
  Lines       27628    27631       +3     
  Branches     4281     4282       +1     
==========================================
+ Hits        17449    17450       +1     
- Misses       9027     9028       +1     
- Partials     1152     1153       +1

Impacted Files	Coverage Δ
src/azure-cli-core/azure/cli/core/util.py	66.42% <50%> (-0.75%)	⬇️

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[troydai]

Would be nice to have a test.

[devigned]

damn... @troydai. I knew you were going to say that. I'll add a test.

[troydai]

I'm too predictable.

[derekbekoe]

Looks good but does it work with Python 2 and 3?

$ python
Python 2.7.10 (default, Feb  6 2017, 23:53:20) 
>>> bytes
<type 'str'>
>>> 

$ python3
Python 3.5.1 (v3.5.1:37a07cee5969, Dec  5 2015, 21:12:44) 
>>> bytes
<class 'bytes'>
>>> 

[devigned]

@derekbekoe should be good. I'll prove with a test.

$ az keyvault certificate show --vault-name level1zb4tc -n sp-cert-level1 --query "x509ThumbprintHex" -o tsv
3EF38981A3EAE51D34E06C93D6D074216DD75323
(env27)