Output more error info

__tests__/main.test.ts

@@ -149,9 +149,11 @@ describe('action', () => {
       }
     })
 
-    fetchMock.mockResponseOnce(JSON.stringify({}), { status: 400 })
+    fetchMock.mockResponseOnce('Something went wrong', { status: 400 })
     await main.run()
-    expect(setFailedMock).toHaveBeenCalled()
+    expect(setFailedMock).toHaveBeenCalledWith(
+      'HTTP Error: Something went wrong'
+    )
   })
   it('Should create a new plugin if not found', async () => {
     getInputMock.mockImplementation(name => {

src/extensionstore.ts

@@ -173,7 +173,9 @@ async function request(
     body: data ? JSON.stringify(data) : undefined
   })
   if (!response.ok) {
-    throw new Error(`HTTP Error: ${(response.status, response.statusText)}`)
+    throw new Error(
+      `HTTP Error: ${(response.status, response.statusText, response.body)}`
+    )
   }
   return await response.json()
 }