Fix name typo in the UI option

Author: MohamedAlmaki

Framework/CurveFitting/src/Algorithms/PlotPeakByLogValueHelper.cpp

@@ -169,8 +169,9 @@ void appendInputSpectraToList(std::vector<InputSpectraToFit> &nameList, const st
     } else {
       for (size_t i = 0; i < axis->length(); ++i) {
         int j = axis->spectraNo(i);
+        int wsIdx = static_cast<int>(i);
         if (j == spectrumNumber) {
-          nameList.emplace_back(name, i, j, -1, period, mws);
+          nameList.emplace_back(name, wsIdx, j, -1, period, mws);
           break;
         }
       }

qt/widgets/common/inc/MantidQtWidgets/Common/SequentialFitDialog.ui

@@ -181,7 +181,7 @@
         <bool>false</bool>
        </property>
        <property name="text">
-        <string>Output spectrum vs params</string>
+        <string>Output workspace index vs params</string>
        </property>
       </widget>
      </item>
@@ -244,7 +244,7 @@
             <string>Range</string>
            </property>
            <property name="toolTip">
-            <string>&lt;html&gt;&lt;head/&gt;&lt;body&gt;&lt;p&gt;Sets a range of values on the numeric axis (spectum number incase of a spectra axis) associated with the workspace index. The range is specfied by a start value and an end value and separated by a colon e.g. 2:5&lt;/p&gt;&lt;/body&gt;&lt;/html&gt;</string>
+            <string>&lt;html&gt;&lt;head/&gt;&lt;body&gt;&lt;p&gt;Sets a range of values on the numeric axis (spectrum number incase of a spectra axis) associated with the workspace index. The range is specfied by a start value and an end value and separated by a colon e.g. 2:5&lt;/p&gt;&lt;/body&gt;&lt;/html&gt;</string>
            </property>
           </column>
          </widget>