Fix install-pn-test-server for recent Git security issues (#2323)

A recent-ish security update (git 1:2.39.5-0+deb12u1) broke the ability
to clone a local directory that is owned by another user. This broke
`ssh-install-pn-test-server`:

```
Cloning into bare repository 'physionet-build.git'...
fatal: detected dubious ownership in repository at '/tmp/physionet-tmp.git'
To add an exception for this directory, call:

	git config --global --add safe.directory /tmp/physionet-tmp.git
fatal: Could not read from remote repository.

Please make sure you have the correct access rights
and the repository exists.
```

deploy/test-server/install-pn-test-server

@@ -61,6 +61,9 @@ apt-get install -y \
 ################################################################
 
 if [ -n "$WFDB_REPOSITORY" ]; then
+    if [ -d "$WFDB_REPOSITORY" ]; then
+        git config --global --add safe.directory "$WFDB_REPOSITORY"
+    fi
     git clone "$WFDB_REPOSITORY" $HOME/wfdb
     (
         cd $HOME/wfdb
@@ -70,6 +73,9 @@ if [ -n "$WFDB_REPOSITORY" ]; then
         make -j$(nproc) -Cdata install
     )
     if [ -n "$LIGHTWAVE_REPOSITORY" ]; then
+        if [ -d "$LIGHTWAVE_REPOSITORY" ]; then
+            git config --global --add safe.directory "$LIGHTWAVE_REPOSITORY"
+        fi
         git clone "$LIGHTWAVE_REPOSITORY" $HOME/lightwave
         (
             cd $HOME/lightwave
@@ -119,6 +125,9 @@ su pn -c '
    virtualenv --no-download -ppython3 /physionet/python-env/physionet
    . /physionet/python-env/physionet/bin/activate
 
+   if [ -d "$REPOSITORY" ]; then
+       git config --global --add safe.directory "$REPOSITORY"
+   fi
    git clone --bare "$REPOSITORY" physionet-build.git
    cd /physionet/physionet-build.git
    GIT_WORK_TREE=/physionet/physionet-build git checkout --force "$REVISION_ID"