doc: fix YAML syntax errors

Author: aduh95

doc/api/buffer.md

@@ -1422,7 +1422,7 @@ added:
 changes:
   - version:
     - v14.10.0
-    = v12.19.0
+    - v12.19.0
     pr-url: https://github.com/nodejs/node/pull/34960
     description: This function is also available as `buf.readBigUint64LE()`.
 -->

doc/api/modules.md

@@ -901,7 +901,6 @@ loading.
 ### `module.parent`
 <!-- YAML
 added: v0.1.16
-deprecated: v14.6.0
 deprecated:
   - v12.19.0
   - v14.6.0

doc/api/zlib.md

@@ -488,7 +488,7 @@ These advanced options are available for controlling decompression:
 <!-- YAML
 added: v0.11.1
 changes:
-  - version
+  - version:
     - v14.5.0
     - v12.19.0
     pr-url: https://github.com/nodejs/node/pull/33516