fix(common): Improve common resources limit ratios (#38546)

**Description**
Some users report that the current ratios between requests and limits
where a bit too strict.
This increases the ratio to 20x on CPU and 12x on ram, lowing requests
and increasing limits slightly.

Its important to note that CPU is easier to share among containers, so
has the higher ratio on purpose.
The new ratio allows more room for multithreading on a container

**⚙️ 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
- [ ] 📜 Documentation Changes

**🧪 How Has This Been Tested?**
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**📃 Notes:**
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**✔️ Checklist:**

- [ ] ⚖️ My code follows the style guidelines of this project
- [ ] 👀 I have performed a self-review of my own code
- [ ] #️⃣ I have commented my code, particularly in hard-to-understand
areas
- [ ] 📄 I have made changes to the documentation
- [ ] 🧪 I have added tests to this description that prove my fix is
effective or that my feature works
- [ ] ⬆️ I increased versions for any altered app according to semantic
versioning
- [ ] I made sure the title starts with `feat(chart-name):`,
`fix(chart-name):`, `chore(chart-name):`, `docs(chart-name):` or
`fix(docs):`

**➕ App addition**

If this PR is an app addition please make sure you have done the
following.

- [ ] 🖼️ I have added an icon in the Chart's root directory called
`icon.png`

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---------

Signed-off-by: Kjeld Schouten <info@kjeldschouten.nl>

website/src/content/docs/guides/index.md

@@ -115,7 +115,7 @@ prometheus:
     retentionSize: 50GB
     resources:
       requests:
-        cpu: 100m
+        cpu: 75m
         memory: 500Mi
       limits:
         memory: 2000Mi

website/src/content/docs/guides/ingress/nginx.md

@@ -58,7 +58,7 @@ controller:
     enabled: false
   resources:
     requests:
-      cpu: 100m
+      cpu: 75m
     limits:
       memory: 500Mi
 defaultBackend:
@@ -110,7 +110,7 @@ controller:
     enabled: false
   resources:
     requests:
-      cpu: 100m
+      cpu: 75m
     limits:
       memory: 500Mi
 defaultBackend: