[BUG] Alias of unnamed declaration needs extra semicolon

[JohelEGP]

Title: Alias of unnamed declaration needs extra semicolon.

Minimal reproducer (https://cpp2.godbolt.org/z/TjfMhcKz6):

x :== :i32 = 0;
y: i32 = 0;

Commands:

cppfront main.cpp2
clang++17 -std=c++23 -stdlib=libc++ -lc++abi -pedantic-errors -Wall -Wextra -Wconversion -I . main.cpp

Expected result: Same as x :== :i32 = 0;; (currently?) or x :== (:i32 = 0);.

Actual result and error: main.cpp2(2,1): error: ';' expected at end of alias declaration.

[JohelEGP]

Probably shares the root problem with #537.
Definitely a duplicate of #532.
Actually, they're all duplicates.