Fix typos in comments.

Backpatch to all supported versions, where applicable, to make backpatching
of future fixes go more smoothly.

Josh Soref

Discussion: https://www.postgresql.org/message-id/CACZqfqCf+5qRztLPgmmosr-B0Ye4srWzzw_mo4c_8_B_mtjmJQ@mail.gmail.com

src/pl/plpython/plpy_elog.c

@@ -303,7 +303,7 @@ PLy_traceback(PyObject *e, PyObject *v, PyObject *tb,
 			long		plain_lineno;
 
 			/*
-			 * The second frame points at the internal function, but to mimick
+			 * The second frame points at the internal function, but to mimic
 			 * Python error reporting we want to say <module>.
 			 */
 			if (*tb_depth == 1)

src/pl/plpython/plpy_plpymodule.c

@@ -463,7 +463,7 @@ PLy_output(volatile int level, PyObject *self, PyObject *args, PyObject *kw)
 
 			if (strcmp(keyword, "message") == 0)
 			{
-				/* the message should not be overwriten */
+				/* the message should not be overwritten */
 				if (PyTuple_Size(args) != 0)
 				{
 					PLy_exception_set(PyExc_TypeError, "Argument 'message' given by name and position");

src/pl/plpython/plpy_typeio.h

@@ -43,7 +43,7 @@ typedef union PLyTypeInput
 } PLyTypeInput;
 
 /*
- * Conversion from Python object to a Postgresql Datum.
+ * Conversion from Python object to a PostgreSQL Datum.
  *
  * The 'inarray' argument to the conversion function is true, if the
  * converted value was in an array (Python list). It is used to give a
@@ -78,7 +78,7 @@ typedef union PLyTypeOutput
 	PLyObToTuple r;
 } PLyTypeOutput;
 
-/* all we need to move Postgresql data to Python objects,
+/* all we need to move PostgreSQL data to Python objects,
  * and vice versa
  */
 typedef struct PLyTypeInfo