refactor: a few points from @rwgk

Author: henryiii

.github/ISSUE_TEMPLATE/bug-report.md

@@ -11,6 +11,7 @@ Make sure you've completed the following steps before submitting your issue -- t
 2. Search the [issue tracker][] to verify that this hasn't already been reported. +1 or comment there if it has.
 3. Consider asking first in the [Gitter chat room][].
 4. Include a self-contained and minimal piece of code that reproduces the problem. If that's not possible, try to make the description as clear as possible.
+    a. If possible, make a PR with a new, failing test to give us a starting point to work on!
 
 [documentation]: https://pybind11.readthedocs.io
 [issue tracker]: https://github.com/pybind/pybind11/issues

.github/CONTRIBUTING.md renamed to CONTRIBUTING.md

@@ -128,7 +128,7 @@ cmake --build build --target check
 * `test_cmake_build`: Install / subdirectory tests
 
 If you want to build just a subset of tests, use
-`-DPYBIND11_TEST_OVERRIDE="test_callbacks.cpp;test_picking.cpp"`. If this is
+`-DPYBIND11_TEST_OVERRIDE="test_callbacks.cpp;test_pickling.cpp"`. If this is
 empty, all tests will be built.
 
 ### Formatting

tests/CMakeLists.txt

@@ -84,7 +84,7 @@ set(PYBIND11_TEST_FILES
     test_virtual_functions.cpp)
 
 # Invoking cmake with something like:
-#     cmake -DPYBIND11_TEST_OVERRIDE="test_callbacks.cpp;test_picking.cpp" ..
+#     cmake -DPYBIND11_TEST_OVERRIDE="test_callbacks.cpp;test_pickling.cpp" ..
 # lets you override the tests that get compiled and run.  You can restore to all tests with:
 #     cmake -DPYBIND11_TEST_OVERRIDE= ..
 if(PYBIND11_TEST_OVERRIDE)