fix: remove duplicate securityContext (radius-project#6996)

# Description

When installing the 0.29.0 helm chart, I received an error message:

```
Helm install failed for release radius-system/radius with chart radius@0.29.0: error while running post render on files: map[string]interface {}(nil): yaml: unmarshal errors:
        line 61: mapping key "securityContext" already defined at line 54
```

This PR removed the duplicate key :)

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Issue: radius-project#6997

Signed-off-by: Ivan Josipovic <9521987+IvanJosipovic@users.noreply.github.com>
Signed-off-by: willdavsmith <willdavsmith@gmail.com>

deploy/Chart/templates/rp/deployment.yaml

@@ -73,8 +73,6 @@ spec:
           mountPath: {{ .Values.global.rootCA.mountPath }}
           readOnly: true
         {{- end }}
-        securityContext:
-          allowPrivilegeEscalation: false
         {{- if .Values.rp.resources }}
         resources:{{ toYaml .Values.rp.resources | nindent 10 }}
         {{- end }}