Fix client secret post for client credentials auth#2140

Noravee wants to merge 4 commits intomodelcontextprotocol:v1.xmodelcontextprotocol/python-sdk:v1.xfrom

Noravee:fix-client-secret-post-for-client-credentials-authNoravee/python-sdk:fix-client-secret-post-for-client-credentials-authCopy head branch name to clipboard