fix(build): python 'externally managed' error on linux

Apparently this behavior changed (pypa/pip#11663), and as seen in a
comment on pypa/pip#11381 this is *intended* to annoy people and 'break
workflows'.

Pesky open-source maintainers. Sigh.

The 'motivation' here is fun, too:

> This may pose a critical problem for the integrity of distros, which
> often have package-management tools that are themselves written in
> Python.

Who'd have thought that the 'everything is installed in a global place'
issue Linux distros have can't 'just' be solved by package managers as
suddenly the package managers can break themselves because, like, who
manages the package manager?

Hopefully the `--user` flag will work here and won't somehow not apply
as something in the build process uses a second user or something.

code/tools/ci/build_server_2.sh

@@ -44,7 +44,7 @@ apk add --no-cache curl=7.72.0-r99 libssl1.1 libcrypto1.1 libunwind libstdc++ zl
 apk add --no-cache --virtual .dev-deps lld~=13 curl-dev=7.72.0-r99 clang-dev~=13 clang~=13 build-base linux-headers openssl1.1-compat-dev python3 py3-pip lua5.3 lua5.3-dev mono-reference-assemblies=5.16.1.0-r9991 mono-dev=5.16.1.0-r9991 libmono=5.16.1.0-r9991 mono-corlib=5.16.1.0-r9991 mono=5.16.1.0-r9991 mono-reference-assemblies-4.x=5.16.1.0-r9991 mono-reference-assemblies-facades=5.16.1.0-r9991 mono-csc=5.16.1.0-r9991 mono-runtime=5.16.1.0-r9991 c-ares-dev v8-dev~=9.3 clang-libs~=13 git dotnet6-sdk
 
 # install python deps
-python3 -m pip install ply six Jinja2 MarkupSafe
+python3 -m pip install --user ply six Jinja2 MarkupSafe
 
 # build natives
 if [ "$SKIP_NATIVES" == "" ]; then