fix(overlay): add null checks for window.__swc.warn in test environments

Author: Shipra Gupta

1st-gen/packages/overlay/src/slottable-request-directive.ts

@@ -74,7 +74,7 @@ export class SlottableRequestDirective extends AsyncDirective {
             { signal }
         );
 
-        if (window.__swc.DEBUG) {
+        if (window.__swc?.DEBUG && window.__swc?.warn) {
             window.__swc.warn(
                 undefined,
                 `⚠️  WARNING ⚠️ : The Overlay Trigger Directive is experimental and there is no guarantees behind its usage in an application!! Its API and presence within the library could be changed at anytime. See "sp-overlay" or "Overlay.open()" for a stable API for overlaying content on your application.`,

1st-gen/packages/overlay/src/slottable-request-event.ts

@@ -23,7 +23,7 @@ export class SlottableRequestEvent extends Event {
         this.name = name;
         this.data = data;
         this.slotName = key !== undefined ? `${name}.${key}` : name;
-        if (window.__swc.DEBUG) {
+        if (window.__swc?.DEBUG && window.__swc?.warn) {
             window.__swc.warn(
                 undefined,
                 `⚠️  WARNING ⚠️ : \`slottable-request\` events are experimental and there is no guarantees behind usage of them in an application!! Their shape and presence within the library could be changed at anytime.