Tutorial: Rewrite using conventions enabled by CMake 3.23

This is a full re-write of the CMake Tutorial for CMake 3.23, both
the functionality it provides, as well as the modern workflows that
developers use when interfacing with CMake.

Issue: #22663, #23086, #23799, #26053, #26105, #26153, #26914

Help/guide/tutorial/Step1/Tutorial/CMakeLists.txt

@@ -0,0 +1,2 @@
+# TODO10: Move all the Tutorial target commands to this CMakeLists.txt. Ensure
+#          that all paths are updated to be relative to this new location.

Help/guide/tutorial/Step1/Tutorial/Tutorial.cxx

@@ -0,0 +1,23 @@
+// A simple program that computes the square root of a number
+#include <cmath>
+#include <iostream>
+#include <string>
+
+// TODO8: Include the MathFunctions header
+
+int main(int argc, char* argv[])
+{
+  if (argc < 2) {
+    std::cout << "Usage: " << argv[0] << " number" << std::endl;
+    return 1;
+  }
+
+  // convert input to double
+  double const inputValue = std::stod(argv[1]);
+
+  // TODO9: Use the mathfunctions::sqrt function
+  // calculate square root
+  double const outputValue = std::sqrt(inputValue);
+  std::cout << "The square root of " << inputValue << " is " << outputValue
+            << std::endl;
+}