Document [GHC 59155] aka TcRnIllegalTupleSection (#510)

* Fill-in the template with stub data

* Add examples from GHC's unit tests

* Small changes

---------

Co-authored-by: David Binder <[email protected]>

Author: geo2a

message-index/messages/GHC-59155/example1/after/IllegalTupleSection.hs

@@ -0,0 +1,6 @@
+{-# LANGUAGE Haskell2010 #-}
+{-# LANGUAGE TupleSections #-}
+
+module IllegalTupleSection where
+
+foo = (1,)

message-index/messages/GHC-59155/example1/before/IllegalTupleSection.hs

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+{-# LANGUAGE Haskell2010 #-}
+-- TupleSections not enabled
+
+module IllegalTupleSection where
+
+foo = (1,)
+

message-index/messages/GHC-59155/example1/index.md

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+---
+title: Illegal tuple section
+---
+
+## Error message
+
+```
+IllegalTupleSection.hs:6:7: error: [GHC-59155]
+    Illegal tuple section
+    Suggested fix:
+      Perhaps you intended to use the ‘TupleSections’ extension
+  |
+6 | foo = (1,)
+  |       ^^^^
+```

message-index/messages/GHC-59155/example2/after/IllegalUnboxedTupleSection.hs

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+{-# LANGUAGE Haskell2010 #-}
+{-# LANGUAGE UnboxedTuples #-}
+{-# LANGUAGE TupleSections #-}
+
+module IllegalUnboxedTupleSection where
+
+foo = (# 1, #)
+

message-index/messages/GHC-59155/example2/before/IllegalUnboxedTupleSection.hs

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+{-# LANGUAGE Haskell2010 #-}
+{-# LANGUAGE UnboxedTuples #-}
+-- TupleSections not enabled
+
+module IllegalUnboxedTupleSection where
+
+foo = (# 1, #)
+

message-index/messages/GHC-59155/example2/index.md

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+---
+title: Illegal unboxed tuple section
+---
+
+## Error message
+
+```
+IllegalTupleSection.hs:7:7: error: [GHC-59155]
+    Illegal tuple section
+    Suggested fix:
+      Perhaps you intended to use the ‘TupleSections’ extension
+  |
+7 | foo = (# 1, #)
+  |       ^^^^^^^^
+```

message-index/messages/GHC-59155/index.md

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+---
+title: Illegal tuple section
+summary: A tuple section is used, but the TupleSections extension is not enabled
+severity: error
+introduced: 9.6.1
+---
+
+One of the components in a tuple is missing, but the `TupleSections` GHC extension has not been enabled. Perhaps this is a typo? If not, and the use of the tuple section syntax is intentional, please enable the extension, for example by adding the following line:
+
+```
+{-# LANGUAGE TupleSections #-}
+```
+
+at the top of your file.
+
+Please refer to the [`TupleSections` section](https://ghc.gitlab.haskell.org/ghc/doc/users_guide/exts/tuple_sections.html?highlight=tuplesection#extension-TupleSections) page of the GHC user guide to learn more about tuple sections.