Update README.md to remove outdated references to the Intel conda environment.

[cmnbroad]

There is only a single conda environment now; remove dangling references to the intel conda environment from the README.md.

[droazen]

👍 Merge when ready @cmnbroad

[cmnbroad]

@bhanugandham @sooheelee BTW, this tutorial is bit out of date - it refers to tools by names that no longer exist (ie. NeuralNetInference -> CNNscoreVariants).

[codecov-io]

Codecov Report

Merging #5753 into master will decrease coverage by 6.693%.
The diff coverage is n/a.

@@               Coverage Diff               @@
##              master     #5753       +/-   ##
===============================================
- Coverage     86.982%   80.288%   -6.693%     
+ Complexity     31860     30238     -1622     
===============================================
  Files           1943      1943               
  Lines         146770    146770               
  Branches       16224     16224               
===============================================
- Hits          127663    117839     -9824     
- Misses         13194     23217    +10023     
+ Partials        5913      5714      -199

Impacted Files	Coverage Δ	Complexity Δ
...kers/filters/VariantFiltrationIntegrationTest.java	0.826% <0%> (-99.174%)	1% <0%> (-25%)
...dorientation/CollectF1R2CountsIntegrationTest.java	0.917% <0%> (-99.083%)	1% <0%> (-12%)
.../walkers/bqsr/BaseRecalibratorIntegrationTest.java	1.031% <0%> (-98.969%)	1% <0%> (-7%)
...ers/vqsr/FilterVariantTranchesIntegrationTest.java	1.053% <0%> (-98.947%)	1% <0%> (-5%)
...s/variantutils/VariantsToTableIntegrationTest.java	1.205% <0%> (-98.795%)	1% <0%> (-20%)
...ientation/ReadOrientationModelIntegrationTest.java	1.667% <0%> (-98.333%)	1% <0%> (-5%)
...on/FindBreakpointEvidenceSparkIntegrationTest.java	1.754% <0%> (-98.246%)	1% <0%> (-6%)
...bender/tools/spark/PileupSparkIntegrationTest.java	2.041% <0%> (-97.959%)	2% <0%> (-13%)
...tute/hellbender/tools/FlagStatIntegrationTest.java	2.083% <0%> (-97.917%)	1% <0%> (-5%)
...rs/variantutils/SelectVariantsIntegrationTest.java	0.25% <0%> (-97.75%)	1% <0%> (-70%)
... and 153 more

[bhanugandham]

@cmnbroad Thank you, I will look into it.

[bhanugandham]

@cmnbroad I have updated the document: https://software.broadinstitute.org/gatk/documentation/article?id=12836