Path for loading files in same repo as kotlin DSL

I want to load scripts into my script section of a build from an external file.  The file is included with the rest of my .teamcity directory in my repo.  I am importing file to load the contents of the file during the DSL run.  I have chosen to import scripts instead of pasting them into the DSL as a string so that I can still execute and test them without copying/pasting etc... It also comes with the benefits of editors keeping debugging/syntax highlighting/etc.. when working with the script file.

My path looks like this:

.teamcity
├── Build
│   ├── Project.kt
│   ├── buildTypes
│   │   ├── Build_Build.kt
│   │   └── cool_script.sh
│   ├── settings.kts
│   └── vcsRoots
│       └── Build_GitGithubComBuildGit.kt
├── Build_dsl.iml
├── pom.xml

My DSL looks like this:

import java.io.File
import jetbrains.buildServer.configs.kotlin.v2017_2.*
import jetbrains.buildServer.configs.kotlin.v2017_2.buildSteps.script

object Devops_Teamcity_Metarunners_Build : BuildType({
    uuid = ""
    id = "Build"
    name = "Build"
    description = "Build Stuff"

    vcs {
        root(Build.vcsRoots.Build_GitGithubComBuildGit)
    }

    steps {
        script {
            name = "Run this cool script"
            scriptContent = File("./cool_script.sh").readText()
        }
    }

When I load this DSL in TeamCity, I get this error:

Current Status:
[16:17:01]:     Failed to apply changes from VCS to project settings (revision 237fa4ebcdb148a54277d263257196094e9ae15c): java.lang.reflect.InvocationTargetException. Please fix the errors in VCS and commit again.
Build: Build.buildTypes.Build_Build$1$2$3 [30]: java.io.FileNotFoundException: ./cool_script.sh (No such file or directory)

So now I am left wondering where this file actually lives in relation to the "working space" of the DSL execution task and how to target it.