fix(site/docs): helm CRD installation section heading spelling error (envoyproxy#1292)

**Description**

Fix typo in "Installing CRDs separately" section

**Related Issues/PRs (if applicable)**

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**Special notes for reviewers (if applicable)**
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Signed-off-by: Tim Swanson <[email protected]>
Co-authored-by: Takeshi Yoneda <[email protected]>
Signed-off-by: Hrushikesh Patil <[email protected]>

Author: 2 people

site/docs/getting-started/installation.md

@@ -24,7 +24,7 @@ kubectl wait --timeout=2m -n envoy-ai-gateway-system deployment/ai-gateway-contr
 
 > If you are experiencing network issues with `docker.io` , you can install the helm chart from the code repo [ai-gateway-helm](https://github.com/envoyproxy/ai-gateway/tree/main/manifests/charts/ai-gateway-helm) instead.
 
-### Installing CRDs serperately
+### Installing CRDs separately
 
 If you want to manage the CRDs separately, install the CRD Helm chart (`ai-gateway-crds-helm`) which will install just the CRDs: