Make argument singular to fix i18n issue

Reported at Transifex.
See https://www.transifex.com/nextcloud/nextcloud/translate/#hu_HU/client/309577611

Signed-off-by: rakekniven <2069590+rakekniven@users.noreply.github.com>

src/libsync/discovery.cpp

@@ -487,7 +487,7 @@ void ProcessDirectoryJob::processFileAnalyzeRemoteInfo(
         if (serverEntry.size == -1)
             missingData.append(tr("size"));
         if (serverEntry.remotePerm.isNull())
-            missingData.append(tr("permissions"));
+            missingData.append(tr("permission"));
         if (serverEntry.etag.isEmpty())
             missingData.append("ETag");
         if (serverEntry.fileId.isEmpty())
@@ -495,7 +495,7 @@ void ProcessDirectoryJob::processFileAnalyzeRemoteInfo(
         if (!missingData.isEmpty()) {
             item->_instruction = CSYNC_INSTRUCTION_ERROR;
             _childIgnored = true;
-            item->_errorString = tr("server reported no %1").arg(missingData.join(QLatin1String(", ")));
+            item->_errorString = tr("Server reported no %1").arg(missingData.join(QLatin1String(", ")));
             emit _discoveryData->itemDiscovered(item);
             return;
         }

test/testremotediscovery.cpp

@@ -169,7 +169,7 @@ private slots:
         QCOMPARE(completeSpy.findItem("nopermissions/A")->_instruction, CSYNC_INSTRUCTION_ERROR);
         QVERIFY(completeSpy.findItem("noetag")->_errorString.contains("ETag"));
         QVERIFY(completeSpy.findItem("nofileid")->_errorString.contains("file id"));
-        QVERIFY(completeSpy.findItem("nopermissions/A")->_errorString.contains("permissions"));
+        QVERIFY(completeSpy.findItem("nopermissions/A")->_errorString.contains("permission"));
     }
 };