Update one more link in README after move to JuliaData

[robert-wright]

I noticed a broken link in the README to the docs which I updated in this PR.

[quinnj]

Thanks!

[codecov]

Codecov Report

Merging #287 (7e8d05c) into main (2e97b48) will increase coverage by 0.24%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main     #287      +/-   ##
==========================================
+ Coverage   87.43%   87.67%   +0.24%     
==========================================
  Files          15       15              
  Lines        1695     1737      +42     
==========================================
+ Hits         1482     1523      +41     
- Misses        213      214       +1     

Impacted Files	Coverage Δ
src/IndexedTables.jl	83.33% <0.00%> (-2.39%)	⬇️
src/reduce.jl	88.63% <0.00%> (-0.60%)	⬇️
src/indexedtable.jl	80.52% <0.00%> (-0.02%)	⬇️
src/reshape.jl	100.00% <0.00%> (ø)
src/join.jl	93.91% <0.00%> (+0.14%)	⬆️
src/utils.jl	71.33% <0.00%> (+0.18%)	⬆️
src/flatten.jl	97.24% <0.00%> (+0.20%)	⬆️
src/ndsparse.jl	87.05% <0.00%> (+0.23%)	⬆️
src/columns.jl	90.12% <0.00%> (+0.32%)	⬆️
src/sortperm.jl	92.50% <0.00%> (+0.39%)	⬆️
... and 2 more

---

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 2e97b48...7e8d05c. Read the comment docs.