Fixes missing comma in User Preset template.

docs/developer/cmake-presets.md

@@ -25,7 +25,7 @@ The following provides preset templates you can build your preset upon.
     A possible user preset for the *Windows* preset:
     ```{.json .copy}
     {
-        "version": 6
+        "version": 6,
         "configurePresets": [
             {
                 "name": "default",
@@ -41,7 +41,7 @@ The following provides preset templates you can build your preset upon.
     A possible user preset for running *MSYS2* on Windows:
     ```{.json .copy}
     {
-        "version": 6
+        "version": 6,
         "configurePresets": [
             {
                 "name": "default",
@@ -57,7 +57,7 @@ The following provides preset templates you can build your preset upon.
     A possible user preset for the *Linux* preset:
     ```{.json .copy}
     {
-        "version": 6
+        "version": 6,
         "configurePresets": [
             {
                 "name": "default",
@@ -78,4 +78,4 @@ cmake -B build -S . --preset default
 ``` 
 
 !!! tip
-    Most **CMake** IDE plugins should recognize these preset files and provide a way for you to select the preset you want.
\ No newline at end of file
+    Most **CMake** IDE plugins should recognize these preset files and provide a way for you to select the preset you want.