fix(BaseNode): change dir for startup script from /tmp to $HOME

Fix changes directory for startup script upload from /tmp to $HOME.
The change is required for DB nodes deployed in Cloud where /tmp dir
is mounted with noexec option what makes script execution impossible
there.

As per discussion (#1), for DB nodes deployed in SCT startup_script
can be executed either from $HOME or /tmp.

refs:
#1: #9608

sdcm/cluster.py

@@ -2911,7 +2911,8 @@ def run_cqlsh(self, cmd, keyspace=None, timeout=120, verbose=True, split=False,
         return cqlsh_out if not split else list(map(str.strip, cqlsh_out.stdout.splitlines()))
 
     def run_startup_script(self):
-        startup_script_remote_path = '/tmp/sct-startup.sh'
+        remote_home_dir = self.remoter.run("echo $HOME").stdout.strip()
+        startup_script_remote_path = f"{remote_home_dir}/startup_script.sh"
 
         with tempfile.NamedTemporaryFile(mode='w+', delete=False, encoding='utf-8') as tmp_file:
             tmp_file.write(self.test_config.get_startup_script())