misc. typos

Found via `codespell`

docs/advanced/exceptions.rst

@@ -138,5 +138,5 @@ section.
     error return without exception set``.
 
     Exceptions that you do not plan to handle should simply not be caught, or
-    may be explicity (re-)thrown to delegate it to the other,
+    may be explicitly (re-)thrown to delegate it to the other,
     previously-declared existing exception translators.

docs/advanced/functions.rst

@@ -126,7 +126,7 @@ targeted arguments can be passed through the :class:`cpp_function` constructor:
 
 .. warning::
 
-    Code with invalid return value policies might access unitialized memory or
+    Code with invalid return value policies might access uninitialized memory or
     free data structures multiple times, which can lead to hard-to-debug
     non-determinism and segmentation faults, hence it is worth spending the
     time to understand all the different options in the table above.

tests/test_exceptions.cpp

@@ -9,7 +9,7 @@
 
 #include "pybind11_tests.h"
 
-// A type that should be raised as an exeption in Python
+// A type that should be raised as an exception in Python
 class MyException : public std::exception {
 public:
     explicit MyException(const char * m) : message{m} {}

tests/test_operator_overloading.py

@@ -98,7 +98,7 @@ def test_nested():
 
     del c
     pytest.gc_collect()
-    del a  # Should't delete while abase is still alive
+    del a  # Shouldn't delete while abase is still alive
     pytest.gc_collect()
 
     assert abase.value == 42

tools/FindPythonLibsNew.cmake

 # - Find python libraries
-# This module finds the libraries corresponding to the Python interpeter
+# This module finds the libraries corresponding to the Python interpreter
 # FindPythonInterp provides.
 # This code sets the following variables:
 #