fix rounding in xml generation str rpr is correct xml is one digit missing

</dcc:quantity>
<dcc:quantity refType="vib_magnitudeTransferCoefVoltage">
<dcc:name>
<dcc:content lang="es">Sensibilidad</dcc:content>
<dcc:content lang="de">Sensitivität</dcc:content>
<dcc:content lang="en">Sensitivity</dcc:content>
</dcc:name>
<si:realListXMLList>
<si:valueXMLList>102.1 102.1 102.1 102.1 102.1 102.1 102.1 102.1 102.1 102.1 102.1 102.1 102.1 102.15 102.20 102.28 102.42 102.64 103.00 103.61 104.52 105.97 108.55</si:valueXMLList>
<si:unitXMLList>\mili\volt\per\metre\second\tothe{-2}</si:unitXMLList>
<si:expandedUncXMLList>
<si:uncertaintyXMLList>0.6 0.6 0.6 0.6 0.6 0.6 0.6 0.6 0.6 0.6 0.6 0.6 0.6 0.31 0.31 0.31 0.31 0.31 0.31 0.31 0.31 0.32 0.33</si:uncertaintyXMLList>
<si:coverageFactorXMLList>2.0</si:coverageFactorXMLList>
<si:coverageProbabilityXMLList>0.95</si:coverageProbabilityXMLList>
<si:distributionXMLList/>
</si:expandedUncXMLList>
</si:realListXMLList>
<dcc:relativeUncertainty>
<dcc:relativeUncertaintyXmlList>
<si:valueXMLList>0.0055000000000000005 0.0055000000000000005 0.0055000000000000005 0.0055000000000000005 0.0055000000000000005 0.0055000000000000005 0.0055000000000000005 0.0055000000000000005 0.0055000000000000005 0.0055000000000000005 0.005500000000000001 0.0055000000000000005 0.0055000000000000005 0.003 0.003 0.003 0.0030000000000000005 0.003 0.003 0.003 0.003 0.0029999999999999996 0.003</si:valueXMLList>
<si:unitXMLList>\one</si:unitXMLList>
</dcc:relativeUncertaintyXmlList>
</dcc:relativeUncertainty>
</dcc:quantity>

Sensitivity in \mili\volt\per\metre\second\tothe{-2} len=23 102.09+/-0.56 102.09+/-0.56 102.09+/-0.56 102.09+/-0.56 ... 108.55+/-0.33 105.97+/-0.32 104.52+/-0.31 103.61+/-0.31

round rel uncer as well.