Update Readme and doc website to reflect deprecated status (#224)

Author: adrain-cb

.github/workflows/hygeine.yml

@@ -36,22 +36,4 @@ jobs:
         uses: golangci/golangci-lint-action@v3
         with:
           # Optional: version of golangci-lint to use in form of v1.2 or v1.2.3 or `latest` to use the latest version
-          version: v1.52.1
-
-  markdown-linting:
-    runs-on: ubuntu-latest
-
-    steps:
-    - name: Check out code
-      uses: actions/checkout@v3
-
-    - name: Set up Node.js
-      uses: actions/setup-node@v2
-      with:
-        node-version: '20'
-        
-    - name: Install markdownlint CLI
-      run: npm install -g markdownlint-cli
-
-    - name: Run markdownlint
-      run: markdownlint '**/*.md'
+          version: v1.52.1

README.md

@@ -1,5 +1,7 @@
 # pessimism
 
+### As of May 28, 2024, Pessimism has been deprecated and is no longer being actively maintained
+
 ## Because you can't always be optimistic
 
 _Pessimism_ is a public good monitoring service that allows for [OP Stack](https://stack.optimism.io/)

docs/index.markdown

@@ -2,6 +2,8 @@
 layout: home
 ---
 
+### As of May 28, 2024, Pessimism has been deprecated and is no longer being actively maintained
+
 Detect real-time threats on Op-stack compatible chains
 
 ## Contents