Failing to compile with ICU support error on Ubuntu

Hi,

I am trying to build the latest postgresql on my ubuntu docker instance.
But its failing to compile it even when ICU related libraries are installed.

Compilation fails with
```
checking whether to build with ICU support... yes
checking for icu-uc icu-i18n... no
configure: error: ICU library not found
If you have ICU already installed, see config.log for details on the
failure. It is possible the compiler isn't looking in the proper directory.
Use --without-icu to disable ICU support.
```

config.log has following error
```
configure:8442: error: ICU library not found
```

I am running on (my docker instance is)
```
$ cat /etc/lsb-release
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=23.04
DISTRIB_CODENAME=lunar
DISTRIB_DESCRIPTION="Ubuntu 23.04"
```

And when I checked, it looks like icu related libraries are there too
```
$ sudo apt-get install icu-devtools libicu-dev libicu72
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
icu-devtools is already the newest version (72.1-3ubuntu2).
libicu-dev is already the newest version (72.1-3ubuntu2).
libicu72 is already the newest version (72.1-3ubuntu2).
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
```

I am pretty new to postgresql's source code and don't yet know whats the
use of ICU libs. So I tried building it with --without-icu and it worked.
But I am not able to figure out whats going wrong here with ICU libs. It
would be good if I can get a proper, clean build.

Thanks,
Siddharth