Fix quick diff for workspace with multiple git repos (microsoft#176390) (microsoft#176524)

* Fix quick diff for workspace with multiple git repos
Part of microsoft#176051

* PR feedback

Author: alexr00

src/vs/workbench/contrib/scm/common/quickDiffService.ts

@@ -59,9 +59,11 @@ export class QuickDiffService extends Disposable implements IQuickDiffService {
 	}
 
 	async getQuickDiffs(uri: URI, language: string = '', isSynchronized: boolean = false): Promise<QuickDiff[]> {
-		const sorted = Array.from(this.quickDiffProviders).sort(createProviderComparer(uri));
+		const providers = Array.from(this.quickDiffProviders)
+			.filter(provider => !provider.rootUri || isEqualOrParent(uri, provider.rootUri))
+			.sort(createProviderComparer(uri));
 
-		const diffs = await Promise.all(Array.from(sorted.values()).map(async (provider) => {
+		const diffs = await Promise.all(providers.map(async provider => {
 			const scoreValue = provider.selector ? score(provider.selector, uri, language, isSynchronized, undefined, undefined) : 10;
 			const diff: Partial<QuickDiff> = {
 				originalResource: scoreValue > 0 ? withNullAsUndefined(await provider.getOriginalResource(uri)) : undefined,