Move spotless.version property to BOM

It is used in the `java8-tests` profile of the BOM.

Author: ppkarwasz

log4j-parent/pom.xml

@@ -108,7 +108,6 @@
     <jeromq.version>0.6.0</jeromq.version>
     <jmdns.version>3.6.0</jmdns.version>
     <jmh.version>1.37</jmh.version>
-    <jspecify.version>1.0.0</jspecify.version>
     <junit.version>4.13.2</junit.version>
     <junit-jupiter.version>5.11.4</junit-jupiter.version>
     <junit-pioneer.version>1.9.1</junit-pioneer.version>

pom.xml

@@ -357,6 +357,7 @@
     <!-- =====================================================
          Direct dependency version properties (in alphabetical order)
          ===================================================== -->
+    <jspecify.version>1.0.0</jspecify.version>
     <log4j-docgen.version>0.9.0</log4j-docgen.version>
     <node.version>21.7.1</node.version>
     <npm.version>10.5.0</npm.version>
@@ -993,6 +994,7 @@
           <groupId>org.jspecify</groupId>
           <artifactId>jspecify</artifactId>
           <version>${jspecify.version}</version>
+          <scope>test</scope>
         </dependency>
       </dependencies>