Remove `charset=utf-8` from ACME certificate requests

acme/api/handler.go

@@ -394,6 +394,6 @@ func GetCertificate(w http.ResponseWriter, r *http.Request) {
 	}
 
 	api.LogCertificate(w, cert.Leaf)
-	w.Header().Set("Content-Type", "application/pem-certificate-chain; charset=utf-8")
+	w.Header().Set("Content-Type", "application/pem-certificate-chain")
 	w.Write(certBytes)
 }

acme/api/handler_test.go

@@ -514,7 +514,7 @@ func TestHandler_GetCertificate(t *testing.T) {
 				assert.Equals(t, res.Header["Content-Type"], []string{"application/problem+json"})
 			} else {
 				assert.Equals(t, bytes.TrimSpace(body), bytes.TrimSpace(certBytes))
-				assert.Equals(t, res.Header["Content-Type"], []string{"application/pem-certificate-chain; charset=utf-8"})
+				assert.Equals(t, res.Header["Content-Type"], []string{"application/pem-certificate-chain"})
 			}
 		})
 	}