fix(web-app-template): Fix webAppRuleViolation.package.id typeError

Evaluator allows policy rule violations without a package see [1],
however this case was not supported in the data mapping from
`WebAppRuleViolation` to Ant Design table row data.

Fixes #9880.

[1]: https://github.com/oss-review-toolkit/ort/blob/cc6f09d/model/src/main/kotlin/RuleViolation.kt#L33

Signed-off-by: Thomas Steenbergen <[email protected]>

Author: tsteenbe

plugins/reporters/web-app-template/src/components/RuleViolationsTable.jsx

@@ -55,7 +55,8 @@ const RuleViolationsTable = ({ webAppRuleViolations = [], showExcludesColumn = t
                         isResolved: webAppRuleViolation.isResolved,
                         key: webAppRuleViolation.key,
                         message: webAppRuleViolation.message,
-                        packageId: webAppRuleViolation.package.id,
+                        packageId: webAppRuleViolation.package 
+                            ? webAppRuleViolation.package.id : '',
                         rule: webAppRuleViolation.rule,
                         severity: webAppRuleViolation.severity,
                         severityIndex: webAppRuleViolation.severityIndex,