sampled_data/**/top_pagview.png should be top_pageview.png

[acmiyaguchi]

See https://github.com/acmiyaguchi/cs229-f19-wiki-forecast/blob/8f1765ad8c29688a0ea2b1c9ddc493b182804143/sample_data/trial_5/top_pagview.png

This needs to be fixed within summarize-pageview. Test the fix by running:

for i in {0..6}; do
    # rerun a specific trial
    artifact_path="sample_data/trial_$i"
    artifact="--artifact-path $artifact_path"
    seed=$(cat $artifact_path/seed.txt | cut -d, -f1)
    hops=$(cat $artifact_path/seed.txt | cut -d, -f3)
    scripts/run-command subgraph sample --article-seed $seed --k-hops $hops $artifact
    scripts/run-command subgraph summarize-graph $artifact
    scripts/run-command subgraph pageview $artifact
    scripts/run-command subgraph summarize-pageview $artifact
done