Add Implementation Report fields to metadata for JS and Web API specs

Also needed for CR generation

Author: dschuff

document/js-api/index.bs

@@ -7,6 +7,7 @@ Issue Tracking: GitHub https://github.com/WebAssembly/spec/issues
 Level: 2
 TR: https://www.w3.org/TR/wasm-js-api-2/
 ED: https://webassembly.github.io/spec/js-api/
+Implementation Report: https://webassembly.org/features/
 Editor: Ms2ger, w3cid 46309, Igalia
 Repository: WebAssembly/spec
 Markup Shorthands: css no, markdown yes

document/web-api/index.bs

@@ -7,6 +7,7 @@ Issue Tracking: GitHub https://github.com/WebAssembly/spec/issues
 Level: 2
 TR: https://www.w3.org/TR/wasm-web-api-2/
 ED: https://webassembly.github.io/spec/web-api/
+Implementation Report: https://webassembly.org/features/
 Editor: Ms2ger, w3cid 46309, Igalia
 Repository: WebAssembly/spec
 Abstract: This document describes the integration of WebAssembly with the broader web platform.