`ar` in Flatpak fails: missing libsframe.so.1 (copied /usr/bin/ar into /app without libsframe)

Inside the flatpak shell, running /app/bin/ar fails due to a missing libsframe soname:
```
sh-5.2$ ar
ar: error while loading shared libraries: libsframe.so.1: cannot open shared object file: No such file or directory
sh-5.2$ which ar
/app/bin/ar
sh-5.2$ ls -l /app/bin/ar
-rwxr-xr-x. 2 nfsnobody nfsnobody 75456 1970-01-01 /app/bin/ar
sh-5.2$ ldd /app/bin/ar
linux-vdso.so.1 (0x00007f07ffbcd000)
libbfd-2.44.so => /app/lib/libbfd-2.44.so (0x00007f07ffa5b000)
libc.so.6 => /usr/lib/x86_64-linux-gnu/libc.so.6 (0x00007f07ff847000)
libz.so.1 => /usr/lib/x86_64-linux-gnu/libz.so.1 (0x00007f07ff82d000)
/lib64/ld-linux-x86-64.so.2 (0x00007f07ffbcf000)
libsframe.so.1 => not found
sh-5.2$ ls -l /app/lib | grep -i -F sframe
sh-5.2$ ls -l /app/lib | grep -i -F bfd
-rwxr-xr-x. 2 nfsnobody nfsnobody 1428584 1970-01-01 libbfd-2.44.so
sh-5.2$
```

The build script copies `ar` and its dependencies `libbfd` into `/app/bin`
https://github.com/flathub/com.visualstudio.code/blob/0f98512a00cca879c91f2f37f9e6325a4356b545/com.visualstudio.code.yaml#L85-L88
but without `libsframe`