fix unit tests

Author: alexnuttall

frontend/src/__tests__/components/molecules/__snapshots__/PreviewTemplateDetails.test.tsx.snap

@@ -370,6 +370,7 @@ exports[`PreviewTemplateDetailsLetter matches snapshot when proofs are present,
             <li>
               <a
                 class="container"
+                data-testid="proof-link"
                 href="/files/undefined/proofs/template-id/a.pdf"
                 rel="noopener noreferrer"
                 target="_blank"
@@ -401,6 +402,7 @@ exports[`PreviewTemplateDetailsLetter matches snapshot when proofs are present,
             <li>
               <a
                 class="container"
+                data-testid="proof-link"
                 href="/files/undefined/proofs/template-id/b.pdf"
                 rel="noopener noreferrer"
                 target="_blank"

frontend/src/__tests__/components/molecules/__snapshots__/ViewLetterTemplate.test.tsx.snap

@@ -150,6 +150,7 @@ exports[`ViewLetterTemplate component matches submitted snapshot 1`] = `
                   <li>
                     <a
                       class="container"
+                      data-testid="proof-link"
                       href="/files/undefined/proofs/template-id/supplier-proof.pdf"
                       rel="noopener noreferrer"
                       target="_blank"

frontend/src/__tests__/middleware.test.ts

@@ -33,6 +33,11 @@ describe('middleware function', () => {
     const request = new NextRequest(url);
     request.cookies.set('csrf_token', 'some-csrf-value');
 
+    getTokenMock.mockResolvedValueOnce({
+      accessToken: undefined,
+      sub: undefined,
+    });
+
     const response = await middleware(request);
 
     expect(getTokenMock).toHaveBeenCalledWith({ forceRefresh: true });