C++: `@function.outer` does not work for multiple template declarations

[alfaix]

Describe the bug When a C++ function uses more than one template declaration, all but 1 are ignored in @function.outer queries.

To Reproduce

1. Create a C++ file with the following (valid) content:

template <class T>
struct A { template <class U> void foo(U); };

template <class T>
template <class U>
void A<T>::foo(U u) {}

2. Go to the last line
3. Query @function.outer (delete/select/whatever)
4. Result: template <class T> is NOT part of the selection, but it should be. It is part of the definition.

Alternatively, on the same file: 2. Go to the line before last: template <class U> 3. Query the @function.outer object 4. Result: only the function declaration itself (without the template lines) gets selected.

Expected behavior In both cases all 3 last lines should be selected as the @function.outer object.

Output of :checkhealth nvim_treesitter

## Installation
  - WARNING: `tree-sitter` executable not found (parser generator, only needed for :TSInstallFromGrammar, not required for :TSInstall)
  - OK: `node` found v16.15.1 (only needed for :TSInstallFromGrammar)
  - OK: `git` executable found.
  - OK: `cc` executable found. Selected from { vim.NIL, "cc", "gcc", "clang", "cl", "zig" }
    Version: Ubuntu clang version 14.0.5-++20220610081652+4d5dad43b2eb-1~exp1~20220610081739.155
  - OK: Neovim was compiled with tree-sitter runtime ABI version 14 (required >=13). Parsers must be compatible with runtime ABI.

## Parser/Features H L F I J
  - cpp            ✓ ✓ ✓ ✓ ✓ 
  - java           ✓ ✓ . ✓ ✓ 
  - python         ✓ ✓ ✓ ✓ ✓ 
  - c              ✓ ✓ ✓ ✓ ✓ 
  - yaml           ✓ ✓ ✓ ✓ ✓ 
  - json5          ✓ . . . ✓ 
  - jsonc          ✓ ✓ ✓ ✓ ✓ 
  - make           ✓ . . . ✓ 
  - llvm           ✓ . . . . 
  - cmake          ✓ . ✓ . . 
  - proto          ✓ . ✓ . . 
  - json           ✓ ✓ ✓ ✓ . 
  - vim            ✓ ✓ ✓ . ✓ 
  - cuda           ✓ ✓ ✓ ✓ ✓ 
  - javascript     ✓ ✓ ✓ ✓ ✓ 
  - ninja          ✓ . ✓ ✓ . 
  - markdown       ✓ . ✓ . ✓ 
  - lua            ✓ ✓ ✓ ✓ ✓ 
  - toml           ✓ ✓ ✓ ✓ ✓ 
  
  Legend: H[ighlight], L[ocals], F[olds], I[ndents], In[j]ections
         +) multiple parsers found, only one will be used
         x) errors found in the query, try to run :TSUpdate {lang}

Output of nvim --version

NVIM v0.8.0-dev
Build type: Release
LuaJIT 2.1.0-beta3
Compiled by alfaix@ak-pc

Features: +acl +iconv +tui
See ":help feature-compile"

   system vimrc file: "$VIM/sysinit.vim"
  fall-back for $VIM: "/usr/local/share/nvim"

Run :checkhealth for more info

Additional context There can also be more than 2 template declarations per function for nested template structs, though that is much more rare. An example that compiles can be seen on godbolt.

From the looks of it, somewhere right here the parser should be told there may be more than 1 template declaration. I don't really know how to do that, apparently (template_declaration)* is not it.