doc: expand history for conditional exports changes in v12

Fixes: #36162

PR-URL: #42339
Reviewed-By: Jacob Smith <jacob@frende.me>
Reviewed-By: Geoffrey Booth <webadmin@geoffreybooth.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

doc/api/packages.md

@@ -16,11 +16,16 @@ changes:
     - v12.19.0
     pr-url: https://github.com/nodejs/node/pull/34117
     description: Add package `"imports"` field.
+  - version:
+    - v13.7.0
+    - v12.17.0
+    pr-url: https://github.com/nodejs/node/pull/29866
+    description: Unflag conditional exports.
   - version:
     - v13.7.0
     - v12.16.0
     pr-url: https://github.com/nodejs/node/pull/31001
-    description: Unflag conditional exports.
+    description: Remove the `--experimental-conditional-exports` option. In 12.16.0, conditional exports are still behind `--experimental-modules`.
   - version:
     - v13.6.0
     - v12.16.0
@@ -1238,6 +1243,11 @@ changes:
     - v12.20.0
     pr-url: https://github.com/nodejs/node/pull/34718
     description: Add support for `"exports"` patterns.
+  - version:
+    - v13.7.0
+    - v12.17.0
+    pr-url: https://github.com/nodejs/node/pull/29866
+    description: Unflag conditional exports.
   - version:
     - v13.7.0
     - v12.16.0
@@ -1247,7 +1257,7 @@ changes:
     - v13.7.0
     - v12.16.0
     pr-url: https://github.com/nodejs/node/pull/31001
-    description: Remove the `--experimental-conditional-exports` option.
+    description: Remove the `--experimental-conditional-exports` option. In 12.16.0, conditional exports are still behind `--experimental-modules`.
   - version:
     - v13.2.0
     - v12.16.0