Bump slf4j-api from 1.+ to 2.0.0 in /examples

Bumps [slf4j-api](https://github.com/qos-ch/slf4j) from 1.+ to 2.0.0.
- [Release notes](https://github.com/qos-ch/slf4j/releases)
- [Commits](https://github.com/qos-ch/slf4j/commits/v_2.0.0)

---
updated-dependencies:
- dependency-name: org.slf4j:slf4j-api
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

examples/aspectj/weaving/build.gradle

@@ -21,7 +21,7 @@ sourceSets {
 dependencies {
     aspect project(":aspectj:aspect")
 
-    implementation "org.slf4j:slf4j-api:1.+"
+    implementation "org.slf4j:slf4j-api:2.+"
 
     implementation "org.aspectj:aspectjrt:1.9.9.1"
     implementation localGroovy()

examples/lombok/build.gradle

@@ -9,7 +9,7 @@ apply plugin: "io.freefair.lombok"
 
 
 dependencies {
-    implementation "org.slf4j:slf4j-api:1.+"
+    implementation "org.slf4j:slf4j-api:2.+"
 }
 
 sourceSets {

examples/lombok/sonarqube/build.gradle

@@ -7,5 +7,5 @@ apply plugin: "io.freefair.lombok"
 
 
 dependencies {
-    implementation "org.slf4j:slf4j-api:1.+"
+    implementation "org.slf4j:slf4j-api:2.+"
 }