Changing codespell and mergeable ymls to prepare for opensourcing kotlin protos (#8442)

Author: deannagarcia

.github/mergeable.yml

@@ -11,7 +11,7 @@ mergeable:
                 regex: 'release notes: yes'
                 message: 'Please include release notes: yes'
             - must_include:
-                regex: '^(autotools|bazel|c#|c\+\+|cleanup|cmake|conformance tests|integration|go|java|javascript|objective-c|php|protoc|python|ruby)'
+                regex: '^(autotools|bazel|c#|c\+\+|cleanup|cmake|conformance tests|integration|go|java|javascript|objective-c|php|protoc|python|ruby|kotlin)'
                 message: 'Please include at least a language label (e.g., c++, java, python). Or apply one of the following labels: autotools, bazel, cmake, cleanup, conformance tests, integration, protoc.'
           - must_include:
               regex: 'release notes: no'

.github/workflows/codespell.yml

@@ -13,4 +13,4 @@ jobs:
         with:
           check_filenames: true
           skip: ./.git,./conformance/third_party,*.snk,*.pb,*.pb.cc,*.pb.h,./src/google/protobuf/testdata,./objectivec/Tests,./python/compatibility_tests/v2.5.0/tests/google/protobuf/internal
-          ignore_words_list: "alow,alse,ba,cleare,copyable,cloneable,dedup,dur,errorprone,files',fo,fundementals,hel,importd,inout,leapyear,nd,nin,ois,ons,parseable,process',te,testof,ue,unparseable,wasn,wee,gae,keyserver,objext,od"
+          ignore_words_list: "alow,alse,ba,cleare,copyable,cloneable,dedup,dur,errorprone,files',fo,fundementals,hel,importd,inout,leapyear,nd,nin,ois,ons,parseable,process',te,testof,ue,unparseable,wasn,wee,gae,keyserver,objext,od,OptIn"