Help: Make TARGET_BUNDLE[_CONTENT]_DIR examples more precise

The `TARGET_BUNDLE_DIR` and `TARGET_BUNDLE_CONTENT_DIR` generator
expressions produce absolute paths.  Show them in the examples.

Suggested-by: Ben Leadbetter <[email protected]>

Help/manual/cmake-generator-expressions.7.rst

@@ -1019,8 +1019,9 @@ which is just the string ``tgt``.
 
   .. versionadded:: 3.9
 
-  Full path to the bundle directory (``my.app``, ``my.framework``, or
-  ``my.bundle``) where ``tgt`` is the name of a target.
+  Full path to the bundle directory (``/path/to/my.app``,
+  ``/path/to/my.framework``, or ``/path/to/my.bundle``),
+  where ``tgt`` is the name of a target.
 
   Note that ``tgt`` is not added as a dependency of the target this
   expression is evaluated on (see policy :policy:`CMP0112`).
@@ -1030,10 +1031,11 @@ which is just the string ``tgt``.
   .. versionadded:: 3.9
 
   Full path to the bundle content directory where ``tgt`` is the name of a
-  target. For the macOS SDK it leads to ``my.app/Contents``, ``my.framework``,
-  or ``my.bundle/Contents``. For all other SDKs (e.g. iOS) it leads to
-  ``my.app``, ``my.framework``, or ``my.bundle`` due to the flat bundle
-  structure.
+  target.  For the macOS SDK it leads to ``/path/to/my.app/Contents``,
+  ``/path/to/my.framework``, or ``/path/to/my.bundle/Contents``.
+  For all other SDKs (e.g. iOS) it leads to ``/path/to/my.app``,
+  ``/path/to/my.framework``, or ``/path/to/my.bundle`` due to the flat
+  bundle structure.
 
   Note that ``tgt`` is not added as a dependency of the target this
   expression is evaluated on (see policy :policy:`CMP0112`).