Fixed Clang warnings

1. `MuonReadoutGeometryR4/RadialStripDesign.icc`: lambda capture 'this' is not used (triggered warnings in 19 client packages)
2. `DiTauRec/ElMuFinder.h`: unused private data member

MuonSpectrometer/MuonPhaseII/MuonDetDescr/MuonReadoutGeometryR4/MuonReadoutGeometryR4/RadialStripDesign.icc

@@ -83,11 +83,11 @@ namespace MuonGMR4{
         }
         const Eigen::Rotation2D normalRot{(m_reversedStripOrder ? 90 : -90)*Gaudi::Units::deg};
         stripEdgeVecItr itr = std::lower_bound(m_strips.begin(), m_strips.end(), extPos,
-                    [this, & normalRot](const stripEdges& stripPos, const Amg::Vector2D& pos) {                            
-                            const Amg::Vector2D dir = stripPos.fromBottomToTop().unit();
-                            const Amg::Vector2D normal = normalRot * dir;                            
-                            std::optional<double> distFromBotEdge = Amg::intersect<2>(stripPos.bottomMounting(), dir, pos, normal);
-                            return distFromBotEdge.value_or(1.) < 0;
+                    [& normalRot](const stripEdges& stripPos, const Amg::Vector2D& pos) {
+                      const Amg::Vector2D dir = stripPos.fromBottomToTop().unit();
+                      const Amg::Vector2D normal = normalRot * dir;
+                      std::optional<double> distFromBotEdge = Amg::intersect<2>(stripPos.bottomMounting(), dir, pos, normal);
+                      return distFromBotEdge.value_or(1.) < 0;
                     });        
         
         if (itr == m_strips.end() || m_strips.begin() == itr) {
@@ -97,4 +97,4 @@ namespace MuonGMR4{
     }
 } 
 #undef CHECK_STRIPRANGE
-#endif
\ No newline at end of file
+#endif

Reconstruction/DiTauRec/DiTauRec/ElMuFinder.h

 /*
-  Copyright (C) 2002-2022 CERN for the benefit of the ATLAS collaboration
+  Copyright (C) 2002-2024 CERN for the benefit of the ATLAS collaboration
 */
 
 #ifndef DITAUREC_ELMUFINDER_H
@@ -43,7 +43,6 @@ class ElMuFinder : public DiTauToolBase {
     { this, "MuonContainer", "Muons", "" };
   float m_muMinPt;
   float m_muMaxEta;
-  int m_muQual;
 
 };