fix: skip interpolation of array of strings if the style of node is l…

…iteral (#5157)

Resolves #5155

Literal style helps to break a string into new lines.

In Copilot version v1.29 we supported interpolation of sequence of strings. There is caveat here
If the manifest has `Literal Style`(Blocked Scalar)  node i.e 

for example if the manifest contains

```yaml
labels: 
  "test": |
      ["label1","label2"]
```

This will lead to unmarshal errors.



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internal/pkg/manifest/interpolate.go

@@ -74,7 +74,7 @@ func (i *Interpolator) applyInterpolation(node *yaml.Node) error {
 			return err
 		}
 		var s []string
-		if err = json.Unmarshal([]byte(interpolated), &s); err == nil && len(s) != 0 {
+		if err = json.Unmarshal([]byte(interpolated), &s); err == nil && len(s) != 0 && node.Style != yaml.LiteralStyle {
 			seqNode := &yaml.Node{
 				Kind: yaml.SequenceNode,
 			}

internal/pkg/manifest/interpolate_test.go

@@ -54,6 +54,14 @@ image:
   # Docker build arguments. For additional overrides: https://aws.github.io/copilot-cli/docs/manifest/backend-service/#image-build
   location: ${0accountID}.dkr.${repo-provider}.${region}.amazonaws.com/vault/${COPILOT_ENVIRONMENT_NAME}:${tag}
   port: 80
+  labels: |
+    ["label1","label2"]
+  "com.datadoghq.ad.instances": |
+    [
+      {
+        "prometheus_url": "http://metrics",
+      }
+    ]
 
 cpu: 256#${CPU}
 memory: 512    # ${Memory}
@@ -89,6 +97,14 @@ image:
   # Docker build arguments. For additional overrides: https://aws.github.io/copilot-cli/docs/manifest/backend-service/#image-build
   location: ${0accountID}.dkr.${repo-provider}..amazonaws.com/vault/test:latest
   port: 80
+  labels: |
+    ["label1","label2"]
+  "com.datadoghq.ad.instances": |
+    [
+      {
+        "prometheus_url": "http://metrics",
+      }
+    ]
 cpu: 256#512
 memory: 512 # ${Memory}
 variables: