[ResponseOps][Cases]Allow dashes in host names in Observables (elastic#219038)

Closes elastic#218946

## Summary

- changed the GENERIC_REGEX to allow `-` 

<img width="488" alt="Screenshot 2025-04-24 at 10 31 00"
src="https://github.com/user-attachments/assets/57841c74-9e6c-4600-81f4-8b454d1ddec1"
/>

Author: georgianaonoleata1904

x-pack/platform/plugins/shared/cases/common/observables/validators.test.ts

@@ -61,6 +61,12 @@ describe('genericValidator', () => {
 
     expect(result).toBeUndefined();
   });
+
+  it('should return undefined if the value contains dashes', () => {
+    const result = validateGenericValue('valid-value');
+
+    expect(result).toBeUndefined();
+  });
 });
 
 describe('validateDomain', () => {

x-pack/platform/plugins/shared/cases/common/observables/validators.ts

@@ -18,7 +18,7 @@ import {
 } from '../constants';
 
 const DOMAIN_REGEX = /^(?!-)[A-Za-z0-9-]{1,63}(?<!-)\.[A-Za-z]{2,}$/;
-const GENERIC_REGEX = /^[a-zA-Z0-9._:/\\]+$/;
+const GENERIC_REGEX = /^[a-zA-Z0-9._:/\\-]+$/;
 
 export interface ValidationError {
   code: string;