fix(showcase): console errors linked to ruleset (#1005)

## Proposed change

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Please also include relevant motivation and context. List any
dependencies that is required for this change. -->

## Related issues

- 🐛 Fixes #(issue)
- 🚀 Feature #(issue)

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apps/showcase/src/assets/rules/rulesets.json

@@ -18,6 +18,13 @@
             "blockType": "IF_ELSE",
             "condition": {
               "all": [
+                {
+                  "lhs": {
+                    "type": "FACT",
+                    "value": "outboundDate"
+                  },
+                  "operator": "isDefined"
+                },
                 {
                   "lhs": {
                     "type": "FACT",
@@ -89,6 +96,13 @@
             "blockType": "IF_ELSE",
             "condition": {
               "all": [
+                {
+                  "lhs": {
+                    "type": "FACT",
+                    "value": "outboundDate"
+                  },
+                  "operator": "isDefined"
+                },
                 {
                   "lhs": {
                     "type": "FACT",