Metapackage version numbers need to be updated at release time.

This change affects the release management process and release managers.

When tagging a release, the version number in core/lib/Drupal.php is historically the only number that would need to be modified prior to tagging.

That version number now exists in two additional metapackages that are embedded in drupal in composer/Metapackage/CoreRecommended/composer.json and composer/Metapackage/PinnedDevDependencies/composer.json

These versions will automatically be updated to the version in core/lib/Drupal.php if the release manager runs composer update --lock after making the change to the tagged number.

After making the change to the tag and updating the lockfile, the diff should appear like so (in this example, tagging the 8.8.0 release)

diff --git a/composer/Metapackage/CoreRecommended/composer.json b/composer/Metapackage/CoreRecommended/composer.json
index 755b7fe691..55ca7579cb 100644
--- a/composer/Metapackage/CoreRecommended/composer.json
+++ b/composer/Metapackage/CoreRecommended/composer.json
@@ -7,7 +7,7 @@
         "webflo/drupal-core-strict": "*"
     },
     "require": {
-        "drupal/core": "8.8.x-dev",
+        "drupal/core": "8.8.0",
         "asm89/stack-cors": "1.2.0",
         "composer/installers": "v1.7.0",
         "composer/semver": "1.5.0",
diff --git a/composer/Metapackage/PinnedDevDependencies/composer.json b/composer/Metapackage/PinnedDevDependencies/composer.json
index 959b64d6db..4d74ebf6ba 100644
--- a/composer/Metapackage/PinnedDevDependencies/composer.json
+++ b/composer/Metapackage/PinnedDevDependencies/composer.json
@@ -7,7 +7,7 @@
         "webflo/drupal-core-require-dev": "*"
     },
     "require": {
-        "drupal/core": "8.8.x-dev",
+        "drupal/core": "8.8.0",
         "behat/mink": "1.8.0 | 1.7.1.1 | 1.7.x-dev",
         "behat/mink-browserkit-driver": "1.3.3",
         "behat/mink-goutte-driver": "v1.2.1",
diff --git a/core/lib/Drupal.php b/core/lib/Drupal.php
index e00aa1c7b0..c53150c7c0 100644
--- a/core/lib/Drupal.php
+++ b/core/lib/Drupal.php
@@ -82,7 +82,7 @@ class Drupal {
   /**
    * The current system version.
    */
-  const VERSION = '8.8.1-dev';
+  const VERSION = '8.8.0';
 
   /**
    * Core API compatibility.

After committing all three changed files and making the tag, when a release manger changes the value in core/lib/Drupal.php *back* to the -dev version, they should also re-run composer update --lock to reset the metapackages back as well, before making the 'back to dev' commit.