docs: Add CollapsedWave to showcase.md (#643)

migueltorrescosta

2023-12-20 be76da9e95b6744f4934280cb85504371ccc1244

 quartz/plugins/transformers/index.ts

@@ -8,3 +8,4 @@
export { OxHugoFlavouredMarkdown } from "./oxhugofm"
export { SyntaxHighlighting } from "./syntax"
export { TableOfContents } from "./toc"
export { HardLineBreaks } from "./linebreaks"