Format markdown (#3679)

Produced via: `prettier --write --prose-wrap=always $(find -name '*.md' | grep -v vendor | grep -v .github)`

CONTRIBUTING.md

@@ -1,5 +1,5 @@
 # Contribution guidelines
 
 So you want to hack on Knative Serving? Yay! Please refer to Knative's overall
-[contribution guidelines](https://www.knative.dev/contributing/)
-to find out how you can help.
+[contribution guidelines](https://www.knative.dev/contributing/) to find out how
+you can help.

DEVELOPMENT.md

@@ -1,8 +1,8 @@
 # Development
 
 This doc explains how to setup a development environment so you can get started
-[contributing](https://www.knative.dev/contributing/)
-to `Knative Serving`. Also take a look at:
+[contributing](https://www.knative.dev/contributing/) to `Knative Serving`. Also
+take a look at:
 
 - [The pull request workflow](https://www.knative.dev/contributing/contributing/#pull-requests)
 - [How to add and run tests](./test/README.md)
@@ -36,7 +36,6 @@ You must install these tools:
 
 ### Create a cluster and a repo
 
-
 1. [Set up a kubernetes cluster](https://www.knative.dev/docs/install/)
    - Follow an install guide up through "Creating a Kubernetes Cluster"
    - You do _not_ need to install Istio or Knative using the instructions in the
@@ -117,9 +116,9 @@ can easily [clean your cluster up](#clean-up) and try again.
 Your user must be a cluster admin to perform the setup needed for Knative.
 
 The value you use depends on
-[your cluster setup](https://www.knative.dev/docs/install/):
-when using Minikube, the user is your local user; when using GKE, the user is
-your GCP user.
+[your cluster setup](https://www.knative.dev/docs/install/): when using
+Minikube, the user is your local user; when using GKE, the user is your GCP
+user.
 
 ```shell
 # For GCP
@@ -263,7 +262,6 @@ ko delete --ignore-not-found=true \
 
 To access Telemetry see:
 
-
 - [Accessing Metrics](https://www.knative.dev/docs/serving/accessing-metrics/)
 - [Accessing Logs](https://www.knative.dev/docs/serving/accessing-logs/)
 - [Accessing Traces](https://www.knative.dev/docs/serving/accessing-traces/

community/README.md

@@ -1,5 +1,5 @@
 # Knative Community
 
 For community information, see
-[Knative Contributing](https://www.knative.dev/contributing/) on
-the [https://www.knative.dev](https://www.knative.dev/) site.
+[Knative Contributing](https://www.knative.dev/contributing/) on the
+[https://www.knative.dev](https://www.knative.dev/) site.