Fix int64 vertex_t

[Iroy30]

No description provided.

[codecov-commenter]

Codecov Report

Merging #1691 (48eb7e8) into branch-21.08 (f714e3e) will increase coverage by 0.22%.
The diff coverage is 0.00%.

@@               Coverage Diff                @@
##           branch-21.08    #1691      +/-   ##
================================================
+ Coverage         59.77%   59.99%   +0.22%     
================================================
  Files                80       80              
  Lines              3540     3542       +2     
================================================
+ Hits               2116     2125       +9     
+ Misses             1424     1417       -7     

Impacted Files	Coverage Δ
python/cugraph/dask/traversal/bfs.py	25.00% <0.00%> (ø)
python/cugraph/dask/traversal/sssp.py	27.58% <0.00%> (ø)
python/cugraph/_version.py	44.80% <0.00%> (+0.39%)	⬆️
python/cugraph/utilities/utils.py	74.46% <0.00%> (+1.41%)	⬆️
python/cugraph/structure/number_map.py	67.05% <0.00%> (+1.96%)	⬆️

---

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 f714e3e...48eb7e8. Read the comment docs.

[BradReesWork]

@gpucibot merge