Revert "Bump spotless (#126125)"

This reverts commit 1306c6b.

Author: joegallo

build-conventions/build.gradle

@@ -77,7 +77,7 @@ dependencies {
     api buildLibs.apache.rat
     compileOnly buildLibs.checkstyle
     constraints {
-      api("org.eclipse.platform:org.eclipse.osgi:3.18.500") {
+      api("org.eclipse.platform:org.eclipse.osgi:3.18.300") {
         because("Use the same version as we do in spotless gradle plugin at runtime")
       }
     }

gradle/build.versions.toml

@@ -43,7 +43,7 @@ snakeyaml = { group = "org.yaml", name = "snakeyaml", version = { strictly = "2.
 spock-core = { group = "org.spockframework", name="spock-core", version.ref="spock" }
 spock-junit4 = { group = "org.spockframework", name="spock-junit4", version.ref="spock" }
 spock-platform = { group = "org.spockframework", name="spock-bom", version.ref="spock" }
-spotless-plugin = "com.diffplug.spotless:spotless-plugin-gradle:7.0.2"
+spotless-plugin = "com.diffplug.spotless:spotless-plugin-gradle:6.25.0"
 wiremock = "com.github.tomakehurst:wiremock-jre8-standalone:2.23.2"
 xmlunit-core = "org.xmlunit:xmlunit-core:2.8.2"