add missing white spaces

Signed-off-by: hwassman <[email protected]>

Author: Helene

source/messages.py

@@ -52,7 +52,7 @@
        'NoData': 'Empty results received',  # Please check the pmcollector is properly configured and running.
        'NoSensorConfigData': 'No sensor configuration data parsed',
        'NoDataStartNextAttempt': 'No Metadata results received from the pmcollector. Start retry attempt {} in 60s (MAX_ATTEMPTS_COUNT:{})',
-       'NullValues':'Received null values in all data points for {}',
+       'NullValues': 'Received null values in all data points for {}',
        'BucketsizeChange': 'Based on requested downsample value: {} the bucketsize will be set: {}',
        'BucketsizeToPeriod': 'Bucketsize will be set to sensors period: {}',
        'DownsampleAggregation': 'Perform downsample aggregation: {} for metric: {}',