housekeeping: .js -> .jsx file extensions (via #5014)

* housekeeping: `.js` -> `.jsx` where necessary

test/xss/markdown-script-sanitization.jsx

@@ -0,0 +1,36 @@
+/* eslint-env mocha */
+import React from "react"
+import expect from "expect"
+import { render } from "enzyme"
+import Markdown from "components/providers/markdown"
+import { Markdown as OAS3Markdown } from "corePlugins/oas3/wrap-components/markdown.js"
+
+describe("Markdown Script Sanitization", function() {
+  describe("Swagger 2.0", function() {
+    it("sanitizes <script> elements", function() {
+      const str = `script <script>alert(1)</script>`
+      const el = render(<Markdown source={str} />)
+      expect(el.html()).toEqual(`<div class="markdown"><p>script </p>\n</div>`)
+    })
+
+    it("sanitizes <img> elements", function() {
+      const str = `<img src=x onerror="alert('img-in-description')">`
+      const el = render(<Markdown source={str} />)
+      expect(el.html()).toEqual(`<div class="markdown"><p><img src="x"></p>\n</div>`)
+    })
+  })
+
+  describe("OAS 3", function() {
+    it("sanitizes <script> elements", function() {
+      const str = `script <script>alert(1)</script>`
+      const el = render(<OAS3Markdown source={str} />)
+      expect(el.html()).toEqual(`<div class="renderedMarkdown"><p>script </p></div>`)
+    })
+
+    it("sanitizes <img> elements", function() {
+      const str = `<img src=x onerror="alert('img-in-description')">`
+      const el = render(<OAS3Markdown source={str} />)
+      expect(el.html()).toEqual(`<div class="renderedMarkdown"><p><img src="x"></p></div>`)
+    })
+  })
+})