Remove reference to an EC2 instance type. (#812)

* Remove reference to an AWS instance type.

Signed-off-by: dblock <dblock@amazon.com>

* Move auto-TOC to top of doc.

Signed-off-by: dblock <dblock@amazon.com>

DEVELOPER_GUIDE.md

@@ -1,33 +1,41 @@
-# Developer Guide
-
-So you want to contribute code to OpenSearch? Excellent! We're glad you're here. Here's what you need to do.
-
-- [Getting Started](#getting-started)
+- [Developer Guide](#developer-guide)
+  - [Getting Started](#getting-started)
     - [Git Clone OpenSearch Repo](#git-clone-opensearch-repo)
     - [Install Prerequisites](#install-prerequisites)
+      - [JDK 14](#jdk-14)
+      - [Docker](#docker)
     - [Run Tests](#run-tests)
     - [Run OpenSearch](#run-opensearch)
-- [Use an Editor](#use-an-editor)
+  - [Use an Editor](#use-an-editor)
     - [IntelliJ IDEA](#intellij-idea)
     - [Visual Studio Code](#visual-studio-code)
     - [Eclipse](#eclipse)
-- [Project Layout](#project-layout)
-    - [docs](#docs)
-    - [distribution](#distribution)
-    - [libs](#libs)
-    - [modules](#modules)
-    - [plugins](#plugins)
-    - [qa](#qa)
-    - [server](#server)
-    - [test](#test)
-- [Java Language Formatting Guidelines](#java-language-formatting-guidelines)
+  - [Project Layout](#project-layout)
+    - [`docs`](#docs)
+    - [`distribution`](#distribution)
+    - [`libs`](#libs)
+    - [`modules`](#modules)
+    - [`plugins`](#plugins)
+    - [`qa`](#qa)
+    - [`server`](#server)
+    - [`test`](#test)
+  - [Java Language Formatting Guidelines](#java-language-formatting-guidelines)
     - [Editor / IDE Support](#editor--ide-support)
     - [Formatting Failures](#formatting-failures)
-- [Gradle Build](#gradle-build)
+  - [Gradle Build](#gradle-build)
     - [Configurations](#configurations)
-- [Misc](#misc)
+      - [implementation](#implementation)
+      - [api](#api)
+      - [runtimeOnly](#runtimeonly)
+      - [compileOnly](#compileonly)
+      - [testImplementation](#testimplementation)
+  - [Misc](#misc)
     - [git-secrets](#git-secrets)
-- [Submitting Changes](#submitting-changes)
+  - [Submitting Changes](#submitting-changes)
+
+# Developer Guide
+
+So you want to contribute code to OpenSearch? Excellent! We're glad you're here. Here's what you need to do.
 
 ## Getting Started
 
@@ -62,7 +70,7 @@ To run the full suite of tests you will also need `JAVA8_HOME`, `JAVA9_HOME`, `J
 
 OpenSearch uses a Gradle wrapper for its build. Run `gradlew` on Unix systems, or `gradlew.bat` on Windows in the root of the repository.
 
-Start by running the test suite with `gradlew check`. This should complete without errors and takes ~15 minutes on a c5.18xlarge.
+Start by running the test suite with `gradlew check`. This should complete without errors.
 
 ```
 ./gradlew check