Bash script never receives arguments when called from Jenkins pipeline - bash

Question

I'm running a declarative Jenkins pipeline on Ubuntu 18.04 slave. My issue is that whenever I'm trying to provide arguments from a sh step to a bash script, the arguments are not there. When running the exact same commands from either a terminal directly or another script file (similarly how Jenkins does it via temp file) the arguments work fine.
The Jenkinsfile looks something like
pipeline {
agent { label "ubuntu" }
options { timeout(time: 1, unit: 'HOURS') }
stages {
stage('Build') {
steps {
sh """
#!/bin/bash
...
. ./Scripts/install_tools.sh "force"
"""
}
}
}
}
The pipeline itself runs smooth and does what I need it to do. The problem is that when calling install_tools.sh no arguments are found. The script looks something like
#!/bin/bash
echo "Running $0"
echo "Args: $#"
...
The line echo "Args: $#" I have tried also with $* and $1 - Each time the arguments are returned as empty, but only when running from the pipeline. It seems to me that this is related to some Groovy stuff, but I have no clue what.
How do I call a bash script during the pipeline and get the arguments passed properly?

Answer 1

put #!/bin/bash into the first line
sh """#!/bin/bash
. ./Scripts/install_tools.sh "force"
"""
otherwise . (dot) command could have different meaning