docs(blocky): update blocking guide (#29807)

**Description**
Updated blocking guide for blocky

⚒️ Fixes  # 

**⚙️ Type of change**

- [ ] ⚙️ Feature/App addition
- [ ] 🪛 Bugfix
- [ ] ⚠️ Breaking change (fix or feature that would cause existing
functionality to not work as expected)
- [ ] 🔃 Refactor of current code

**🧪 How Has This Been Tested?**

**📃 Notes:**

**✔️ Checklist:**

- [ ] ⚖️ My code follows the style guidelines of this project
- [ ] 👀 I have performed a self-review of my own code
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areas
- [ ] 📄 I have made corresponding changes to the documentation
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- [ ] 🧪 I have added tests to this description that prove my fix is
effective or that my feature works
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versioning
- [ ] I made sure the title starts with `feat(chart-name):`,
`fix(chart-name):` or `chore(chart-name):`

**➕ App addition**

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following.

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`icon.png`

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charts/premium/blocky/docs/setup-guide.md

@@ -104,7 +104,7 @@ bootstrapDns:
 
 ## DNS Blacklists and Whitelists
 
-Blocky comes preconfigured with basic Blacklists and Whitelists (commented out by default). DNS Blacklists are used to prevent DNS resolution of advertisement, malware, trackers and adult sites domains. DNS Whitelists are used to always allow DNS resolution of domains regardless of existing blacklists. This is completed with public maintained blocklists. A good source for these is [firebog.net](https://firebog.net).
+Blocky comes preconfigured with basic Blacklists and Whitelists. DNS Blacklists are used to prevent DNS resolution of advertisement, malware, trackers and adult sites domains. DNS Whitelists are used to always allow DNS resolution of domains regardless of existing blacklists. This is completed with public maintained blocklists. A good source for these is [firebog.net](https://firebog.net).
 
 :::caution
 
@@ -114,21 +114,36 @@ certain blocklists if you find legitimate traffic being blocked.
 
 :::
 
-If you wish to enable or customize the default Block Blacklists or Whitelists follow the example below.
+If you wish to disable the default Blocklist and Whitelist make changes as shown below:
+
+```yaml
+// values.yaml
+blocking:
+  clientGroupsBlock:
+    - name: default
+      groups:
+        []
+```
+
+If you wish to use custom Blacklists or Whitelists follow the example below:
 
 ```yaml
 // values.yaml
 blocking:
   whitelist:
-  - name: default
+  - name: mylist
     lists:
     - https://raw.githubusercontent.com/anudeepND/whitelist/master/domains/optional-list.txt
     - https://raw.githubusercontent.com/anudeepND/whitelist/master/domains/whitelist.txt
     - https://raw.githubusercontent.com/rahilpathan/pihole-whitelist/main/1.LowWL.txt
   blacklist:
-  - name: default
+  - name: mylist
     lists:
     - https://big.oisd.nl/domainswild
+  clientGroupsBlock:
+    - name: default
+      groups:
+        - mylist
 ```
 
 ## Networking