Try resolve git branches beginning with '@' before replacing w… (#66097)

Try resolve git branches beginning with '@' before replacing with symbolic full path

extensions/git/src/git.ts

@@ -1680,13 +1680,16 @@ export class Repository {
 	async getBranch(name: string): Promise<Branch> {
 		if (name === 'HEAD') {
 			return this.getHEAD();
-		} else if (/^@/.test(name)) {
-			const symbolicFullNameResult = await this.run(['rev-parse', '--symbolic-full-name', name]);
-			const symbolicFullName = symbolicFullNameResult.stdout.trim();
-			name = symbolicFullName || name;
 		}
 
-		const result = await this.run(['rev-parse', name]);
+		let result = await this.run(['rev-parse', name]);
+
+		if (!result.stdout && /^@/.test(name)) {
+			const symbolicFullNameResult = await this.run(['rev-parse', '--symbolic-full-name', name]);
+			name = symbolicFullNameResult.stdout.trim();
+
+			result = await this.run(['rev-parse', name]);
+		}
 
 		if (!result.stdout) {
 			return Promise.reject<Branch>(new Error('No such branch'));