Add changelog entry

Author: jhl221123

src/changelog/.2.x.x/3828_fix_log_placeholder_mismatch.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<entry xmlns="https://logging.apache.org/xml/ns"
+       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+       xsi:schemaLocation="
+           https://logging.apache.org/xml/ns
+           https://logging.apache.org/xml/ns/log4j-changelog-0.xsd"
+       type="fixed">
+    <issue id="3828" link="https://github.com/apache/logging-log4j2/issues/3828"/>
+    <description format="asciidoc">
+        Corrected an incorrect placeholder count in the AbstractDriverManagerConnectionSource debug log message to prevent unnecessary warnings.
+    </description>
+</entry>