Fix incorrect PR numbers in ChangeLog (emscripten-core#26106)

I asked Gemini to compare `ChangeLog.md` and `git log` results and fix
all incorrect PR numbers it finds. It ended up fixing several but all of
them are the cases where the PR number does not actually exists (i.e.,
they are issues, not PRs). I think there are many more but it wasn't
able to find the cases where the PR number exists but incorrect.

Anyway, these are the several cases it found.

Author: aheejin

ChangeLog.md

@@ -87,7 +87,7 @@ See docs/process.md for more on how version tagging works.
 - The standalone `file_packager.py` script no longer supports `--embed` with JS
   output (use `--obj-output` is now required for embedding data).  This usage
   has been producing a warning since #16050 which is now an error.  (#25049)
-- Embind now requires C++17 or newer. See #24850.
+- Embind now requires C++17 or newer. (#25773)
 
 4.0.19 - 11/04/25
 -----------------
@@ -182,7 +182,7 @@ See docs/process.md for more on how version tagging works.
   (and `FS_createPreloadedFile` API`) was converted from callbacks to async.
   Any externally managed plugins would need to be updated accordingly.  An
   assertion will detect any such non-async plugins in the wild. (#24914)
-- SDL2 updated from 2.32.0 to 2.32.8. (#24912/)
+- SDL2 updated from 2.32.0 to 2.32.8. (#24912)
 - `sdl-config` and `sdl2-config` scripts were simplified to avoid using python
   and the `.bat` file versions were removed, matching upstream SDL. (#24907)
 - The `addRunDependency`/`removeRunDependency` now assert in debug builds if
@@ -436,7 +436,7 @@ See docs/process.md for more on how version tagging works.
 ----------------
 - Emscripten version was bumped to 4.0.0. Happy new year, happy new major
   version!  While version has a few interesting changes, there is nothing huge
-  that makes it different from any other release. (#19053)
+  that makes it different from any other release. (#23235)
 - `-sWASM_LEGACY_EXCEPTIONS` option is added. (#23365) If true, it will emit
   instructions for the legacy Wasm exception handling proposal
   (https://github.com/WebAssembly/exception-handling/blob/main/proposals/exception-handling/legacy/Exceptions.md),
@@ -1597,7 +1597,7 @@ See docs/process.md for more on how version tagging works.
 - Due to an llvm change (https://reviews.llvm.org/D118573) some clang flags
   that did not previously have any effect are now honored (e.g.
   `-fnew-alignment` and `-fshort-wchar`).
-- llvm dependency updated to 15.0.0 to match upstream. (#16178)
+- llvm dependency updated to 15.0.0 to match upstream. (#16182)
 - The `__EMSCRIPTEN_major__`, `__EMSCRIPTEN_minor__` and `__EMSCRIPTEN_tiny__`
   macros are now available via the `emscripten/version.h` header file.  For the
   time being, unless you enable `-sSTRICT`, these are still also defined
@@ -1778,7 +1778,7 @@ See docs/process.md for more on how version tagging works.
 -------------------
 - Added `EM_ASYNC_JS` macro - similar to `EM_JS`, but allows using `await`
   inside the JS block and automatically integrates with Asyncify without
-  the need for listing the declared function in `ASYNCIFY_IMPORTS` (#9709).
+  the need for listing the declared function in `ASYNCIFY_IMPORTS` (#14728).
 - Errors that occur on pthreads (e.g. uncaught exception) will now get re-thrown
   on the main thread rather than simply being logged (#13666).
 
@@ -2550,7 +2550,7 @@ See docs/process.md for more on how version tagging works.
   a global setting in the emscripten config file that would inject extra
   compiler options.
 - Allow spaces in a path to Python interpreter when running emscripten from Unix
-  shell (#11005).
+  shell (#11006).
 - Support atexit() in standalone mode (#10995). This also fixes stdio stream
   flushing on exit in that mode.