fix: "markdown" should be correctly capitalized

Author: elijah-potter

README.md

@@ -2,25 +2,25 @@
 
 # Quarto
 
-Quarto is an open-source scientific and technical publishing system built on [Pandoc](https://pandoc.org). Quarto documents are authored using [markdown](https://en.wikipedia.org/wiki/Markdown), an easy to write plain text format.
+Quarto is an open-source scientific and technical publishing system built on [Pandoc](https://pandoc.org). Quarto documents are authored using [Markdown](https://en.wikipedia.org/wiki/Markdown), an easy to write plain text format.
 
 In addition to the core capabilities of Pandoc, Quarto includes:
 
 1.  Embedding code and output from Python, R, Julia, and JavaScript via integration with [Jupyter](https://jupyter.org/), [Knitr](https://yihui.org/knitr/), and [Observable](https://github.com/observablehq/).
 
-2.  A variety of extensions to Pandoc markdown useful for technical writing including cross-references, sub-figures, layout panels, hoverable citations and footnotes, callouts, and more.
+2.  A variety of extensions to Pandoc Markdown useful for technical writing including cross-references, sub-figures, layout panels, hoverable citations and footnotes, callouts, and more.
 
 3.  A project system for rendering groups of documents at once, sharing options across documents, and producing aggregate output like [websites](https://quarto.org/docs/websites/) and [books](https://quarto.org/docs/books/).
 
 4.  Authoring using a wide variety of editors and notebooks including [JupyterLab](https://quarto.org/docs/tools/jupyter-lab.html), [RStudio](https://quarto.org/docs/tools/rstudio.html), and [VS Code](https://quarto.org/docs/tools/vscode.html).
 
-5.  A [visual markdown editor](https://quarto.org/docs/visual-editor/) that provides a productive writing interface for composing long-form documents.
+5.  A [visual Markdown editor](https://quarto.org/docs/visual-editor/) that provides a productive writing interface for composing long-form documents.
 
 Learn more about Quarto at <https://quarto.org>.
 
 ## Development Version
 
-To install the development version of the Quarto CLI, clone the quarto-cli repository then run the configure script for your platform (`configure.sh` for Linux/macOS or `configure.cmd` for Windows). For example:
+To install the development version of the Quarto CLI, clone the `quarto-cli` repository then run the configure script for your platform (`configure.sh` for Linux/macOS or `configure.cmd` for Windows). For example:
 
 ```bash
 git clone https://github.com/quarto-dev/quarto-cli