Revert "Re #21749: Use maximum precision when converting to string."

This reverts commit bd6530b5.

I'm reverting the change to precision in Parameter.h for now because this is causing test failures which are out of scope for this PR.

Re #21749

Framework/Geometry/inc/MantidGeometry/Instrument/Parameter.h

@@ -10,7 +10,6 @@
 #include <typeinfo>
 #include <vector>
 #include <stdexcept>
-#include <iomanip>
 
 namespace Mantid {
 
@@ -186,7 +185,6 @@ template <class T> void Parameter::set(const T &t) {
  */
 template <class Type> std::string ParameterType<Type>::asString() const {
   std::ostringstream str;
-  str << std::setprecision(std::numeric_limits<Type>::digits10);
   str << m_value;
   return str.str();
 }