fix: restore env vars in finally block to prevent test pollution

Move environment variable restoration from the try block to a finally
block so env vars passed via the test harness are always cleaned up,
even when the command fails and Deno's exit sanitizer intercepts the
Deno.exit() call.

Without this, a test that sets env vars (e.g. QUARTO_PDF_STANDARD)
via TestContext.env could leak those values to subsequent tests when
running in the same deno test process.

Author: cderv

src/quarto.ts

@@ -196,13 +196,6 @@ export async function quarto(
 
   try {
     await promise;
-    for (const [key, value] of Object.entries(oldEnv)) {
-      if (value === undefined) {
-        Deno.env.delete(key);
-      } else {
-        Deno.env.set(key, value);
-      }
-    }
     if (commandFailed()) {
       exitWithCleanup(1);
     }
@@ -213,6 +206,14 @@ export async function quarto(
     } else {
       throw e;
     }
+  } finally {
+    for (const [key, value] of Object.entries(oldEnv)) {
+      if (value === undefined) {
+        Deno.env.delete(key);
+      } else {
+        Deno.env.set(key, value);
+      }
+    }
   }
 }