test_runner: finish marking snapshot testing as stable

Snapshot testing was marked stable in nodejs#55897. These were
overlooked at the time.

Refs: nodejs#55897

doc/api/test.md

@@ -932,7 +932,13 @@ test('runs timers as setTime passes ticks', (context) => {
 
 ## Snapshot testing
 
-> Stability: 1.0 - Early development
+<!-- YAML
+added: v22.3.0
+changes:
+  - version: v23.4.0
+    pr-url: https://github.com/nodejs/node/pull/55897
+    description: Snapsnot testing is no longer experimental.
+-->
 
 Snapshot tests allow arbitrary values to be serialized into string values and
 compared against a set of known good values. The known good values are known as
@@ -1750,8 +1756,6 @@ describe('tests', async () => {
 added: v22.3.0
 -->
 
-> Stability: 1.0 - Early development
-
 An object whose methods are used to configure default snapshot settings in the
 current process. It is possible to apply the same configuration to all files by
 placing common configuration code in a module preloaded with `--require` or
@@ -1763,8 +1767,6 @@ placing common configuration code in a module preloaded with `--require` or
 added: v22.3.0
 -->
 
-> Stability: 1.0 - Early development
-
 * `serializers` {Array} An array of synchronous functions used as the default
   serializers for snapshot tests.
 
@@ -1780,8 +1782,6 @@ more robust serialization mechanism is required, this function should be used.
 added: v22.3.0
 -->
 
-> Stability: 1.0 - Early development
-
 * `fn` {Function} A function used to compute the location of the snapshot file.
   The function receives the path of the test file as its only argument. If the
   test is not associated with a file (for example in the REPL), the input is
@@ -3261,8 +3261,6 @@ test('test', (t) => {
 added: v22.3.0
 -->
 
-> Stability: 1.0 - Early development
-
 * `value` {any} A value to serialize to a string. If Node.js was started with
   the [`--test-update-snapshots`][] flag, the serialized value is written to
   the snapshot file. Otherwise, the serialized value is compared to the

lib/internal/test_runner/snapshot.js

@@ -15,7 +15,7 @@ const {
     ERR_INVALID_STATE,
   },
 } = require('internal/errors');
-const { emitExperimentalWarning, kEmptyObject } = require('internal/util');
+const { kEmptyObject } = require('internal/util');
 let debug = require('internal/util/debuglog').debuglog('test_runner', (fn) => {
   debug = fn;
 });
@@ -28,7 +28,6 @@ const { strictEqual } = require('assert');
 const { mkdirSync, readFileSync, writeFileSync } = require('fs');
 const { dirname } = require('path');
 const { createContext, runInContext } = require('vm');
-const kExperimentalWarning = 'Snapshot testing';
 const kMissingSnapshotTip = 'Missing snapshots can be generated by rerunning ' +
   'the command with the --test-update-snapshots flag.';
 const defaultSerializers = [
@@ -47,13 +46,11 @@ let resolveSnapshotPathFn = defaultResolveSnapshotPath;
 let serializerFns = defaultSerializers;
 
 function setResolveSnapshotPath(fn) {
-  emitExperimentalWarning(kExperimentalWarning);
   validateFunction(fn, 'fn');
   resolveSnapshotPathFn = fn;
 }
 
 function setDefaultSnapshotSerializers(serializers) {
-  emitExperimentalWarning(kExperimentalWarning);
   validateFunctionArray(serializers, 'serializers');
   serializerFns = ArrayPrototypeSlice(serializers);
 }
@@ -207,7 +204,6 @@ class SnapshotManager {
     const manager = this;
 
     return function snapshotAssertion(actual, options = kEmptyObject) {
-      emitExperimentalWarning(kExperimentalWarning);
       validateObject(options, 'options');
       const {
         serializers = serializerFns,