feat: Improve hover too long parameter list

[A4-Tacks]

Example

fn fn_$0(
    attrs: impl IntoIterator<Item = ast::Attr>,
    visibility: Option<ast::Visibility>,
    fn_name: ast::Name,
    type_params: Option<ast::GenericParamList>,
    where_clause: Option<ast::WhereClause>,
    params: ast::ParamList,
    body: ast::BlockExpr,
    ret_type: Option<ast::RetType>,
    is_async: bool,
    is_const: bool,
    is_unsafe: bool,
    is_gen: bool,
) -> ast::Fn {}

Before this PR

fn fn_(attrs: impl IntoIterator<Item = ast::Attr>, visibility: Option<ast::Visibility>, fn_name: ast::Name, type_params: Option<ast::GenericParamList>, where_clause: Option<ast::WhereClause>, params: ast::ParamList, body: ast::BlockExpr, ret_type: Option<ast::RetType>, is_async: bool, is_const: bool, is_unsafe: bool, is_gen: bool) -> ast::Fn

After this PR

fn fn_(
    attrs: impl IntoIterator<Item = ast::Attr>,
    visibility: Option<ast::Visibility>,
    fn_name: ast::Name,
    type_params: Option<ast::GenericParamList>,
    where_clause: Option<ast::WhereClause>,
    params: ast::ParamList,
    body: ast::BlockExpr,
    ret_type: Option<ast::RetType>,
    is_async: bool,
    is_const: bool,
    is_unsafe: bool,
    is_gen: bool
) -> ast::Fn

[ChayimFriedman2]

Looks nice, thanks!