Using `panicnil=1` restores the behavior of Go 1.20 and earlier.

When compiling a work module or workspace that declares
an older Go version, the Go toolchain amends its defaults
to match that older Go version as closely as possible.
For example, when a Go 1.21 toolchain compiles a program,
if the work module's `go.mod` or the workspace's `go.work`
says `go` `1.20`, then the program defaults to `panicnil=1`,
matching Go 1.20 instead of Go 1.21.

   * cached value, which will be recalculated when {@code get()} is called on the reserialized
   * instance. The actual memoization does not happen when the underlying delegate throws an
   * exception.
   *
   * <p>When the underlying delegate throws an exception then this memoizing supplier will keep
   * delegating calls until it returns valid data.
   *

  // Standard object metadata
  // +optional
  optional k8s.io.apimachinery.pkg.apis.meta.v1.ObjectMeta metadata = 1;

  // Spec describes the desired attributes of a resource that then needs
  // to be allocated. It can only be set once when creating the
  // ResourceClaim.
  optional ResourceClaimSpec spec = 2;

  // Status describes whether the resource is available and with which
  // attributes.
  // +optional

Then, when you create an instance of that `Settings` class (in this case, in the `settings` object), Pydantic will read the environment variables in a case-insensitive way, so, an upper-case variable `APP_NAME` will still be read for the attribute `app_name`.

            currentExpression == ifExpression.then || currentExpression == ifExpression.`else`
        } ?: return null
        getExpectedType(ifExpression)?.let { return it }

        // if `KtIfExpression` doesn't have an expected type, get the expected type of the current branch from the other branch
        val otherBranch = (if (expression == ifExpression.then) ifExpression.`else` else ifExpression.then) ?: return null

   * cached value, which will be recalculated when {@code get()} is called on the reserialized
   * instance. The actual memoization does not happen when the underlying delegate throws an
   * exception.
   *
   * <p>When the underlying delegate throws an exception then this memoizing supplier will keep
   * delegating calls until it returns valid data.
   *

### Single Container

        _ * classDoc.classBlocks >> []
        _ * classDoc.classExtensions >> []
        _ * classDoc.subClasses >> []

        when:
        def result = parse('<root/>')
        withCategories {
            renderer.mergeContent(classDoc, result)
        }

        then:
        formatTree(result) == '''<root>
    <chapter id="classId">
        <title>Class</title>
        <segmentedlist>

    * This doesn't refer to the file, nor to the code, it refers **specifically** to the thing that is being **executed** and managed by the operating system.
* Any program, any code, **can only do things** when it is being **executed**. So, when there's a **process running**.
* The process can be **terminated** (or "killed") by you, or by the operating system. At that point, it stops running/being executed, and it can **no longer do things**.

     * If no module is found, or if module information cannot be extracted, then this constructor
     * builds an empty map.
     *
     * <p>If the {@code resolve} parameter value is {@code false}, then some or all map values may
     * be null instead of the actual module name. This option can avoid the cost of reading module
     * descriptors when only the modules existence needs to be verified.</p>
     *
     * <p><b>Algorithm:</b>