TypeScript: Add missing .tsx extension

Exactly how it is done for JavaScript nowadays:

➜ ctags --list-maps | grep JavaScript                                                                                       
JavaScript *.js *.jsx *.mjs

Seems that this is the file that needs to be changed (but unfortunately I don't dare to change C/C++ code ) https://github.com/universal-ctags/ctags/blob/6928d2b39f82ef80a947ae6a355bd91a803619e2/parsers/typescript.c#L2053

NOTE: For those having this issue, you can mitigate by creating a file called (for instance) tsx.ctags inside your $HOME/.ctags.d folder, with the following content:

--langmap=TypeScript:.ts.tsx

Thank you!