setup.py only reports successful builds if one or more stdlib modules are missing

[erlend-aasland]

"Python build finished successfully!" is only printed if there were missing modules:

cpython/setup.py

Lines 539 to 547 in cf730b5

	if self.missing:
	print()
	print("Python build finished successfully!")
	print("The necessary bits to build these optional modules were not "
	"found:")
	print_three_column(self.missing)
	print("To find the necessary bits, look in setup.py in"
	" detect_modules() for the module's name.")
	print()

Either we print it every time the build succeeds:

diff --git a/setup.py b/setup.py
index 4c497346e8..e87da57a47 100644
--- a/setup.py
+++ b/setup.py
@@ -538,5 +538,9 @@ def print_three_column(lst):
 
-        if self.missing:
+        if not self.failed:
             print()
             print("Python build finished successfully!")
+            print()
+
+        if self.missing:
+            print()
             print("The necessary bits to build these optional modules were not "

Or we just remove that line from setup.py.

I'm fine with either.

Originally reported by @izumiberat in #93659 (comment)

[erlend-aasland]

cc. @tiran

[erlend-aasland]

Come to think of it, we might want to adjust the "To find the necessary bits, look in setup.py in detect_modules() for the module's name." also.