Update org.springframework.data to 2021.2.8

Closes gh-12738

Author: jzheaux

dependencies/spring-security-dependencies.gradle

@@ -11,7 +11,7 @@ dependencies {
 	api platform("io.projectreactor:reactor-bom:2020.0.28")
 	api platform("io.rsocket:rsocket-bom:1.1.3")
 	api platform("org.junit:junit-bom:5.8.2")
-	api platform("org.springframework.data:spring-data-bom:2021.2.6")
+	api platform("org.springframework.data:spring-data-bom:2021.2.8")
 	api platform("org.jetbrains.kotlin:kotlin-bom:$kotlinVersion")
 	api platform("org.jetbrains.kotlinx:kotlinx-coroutines-bom:1.6.4")
 	api platform("com.fasterxml.jackson:jackson-bom:2.13.5")