remove trailing whitespace

Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>

Author: zhumin8

java-showcase/gapic-showcase/pom.xml

@@ -19,7 +19,7 @@
   <properties>
     <gapic-showcase.version>0.36.2</gapic-showcase.version>
     <!-- This is the last version supporting slf4j 1.x, do not upgrade -->
-    <slf4j1-logback.version>1.2.13</slf4j1-logback.version> 
+    <slf4j1-logback.version>1.2.13</slf4j1-logback.version>
     <slf4j2-logback.version>1.5.21</slf4j2-logback.version>
   </properties>