fix: fix invalid plugin manifests

[camilovelezr]

This PR fixes validation errors in the following plugin.json files:

• clustering/k-means-clustering-tool
• clustering/outlier-removal-tool/plugin.json
• dimension_reduction/UMAP/Shared-Memory-GPU/plugin.json
• features/nyxus-tool/plugin.json
• features/region-segmentation-eval-tool/plugin.json
• regression/basic-flatfield-estimation-tool/plugin.json
• segmentation/cell-border-segmentation-tool/plugin.json
• transforms/images/binary-operations-tool/plugin.json
• transforms/images/polus-autocropping-plugin/plugin.json
• transforms/tabular/polus-generalized-linear-model-plugin/plugin.json
• utils/rxiv-download-tool/plugin.json
• visualization/microjson-to-ome-tool/plugin.json
• visualization/ome-to-microjson-tool/plugin.json
• visualization/polus-graph-pyramid-builder-plugin/plugin.json

[camilovelezr]

@hamshkhawar Could you please double check the accuracy of these changes? Especially k-means-clustering-tool? Thank you!