adding url by correcting typo

[estella98]

No description provided.

[codecov]

Codecov Report

Merging #1357 into master will decrease coverage by 0.03%.
The diff coverage is n/a.

@@             Coverage Diff              @@
##             master    #1357      +/-   ##
============================================
- Coverage     51.68%   51.65%   -0.04%     
+ Complexity      802      800       -2     
============================================
  Files           154      154              
  Lines          8627     8627              
  Branches       1224     1224              
============================================
- Hits           4459     4456       -3     
- Misses         3796     3800       +4     
+ Partials        372      371       -1     

Impacted Files	Coverage Δ	Complexity Δ
...java/io/anserini/ltr/feature/CountBigramPairs.java	64.93% <0.00%> (-5.20%)	23.00% <0.00%> (-3.00%)
...anserini/ltr/feature/base/PMIFeatureExtractor.java	86.53% <0.00%> (+1.92%)	13.00% <0.00%> (+1.00%)

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 04ef3bb...f346dbe. Read the comment docs.

[lintool]

hi @estella98 - sorry I didn't carefully check, but your commit doesn't seem to refer to a valid commit id? Should point to the commit point at which you ran the code...