Add shibboleth.net Maven repository

This is necessary for opensaml 4.1.0

Issue gh-9539

Author: rwinch

buildSrc/src/main/groovy/io/spring/gradle/convention/RepositoryConventionPlugin.groovy

@@ -74,6 +74,10 @@ class RepositoryConventionPlugin implements Plugin<Project> {
 				}
 				url = 'https://repo.spring.io/release/'
 			}
+			maven {
+				name = 'shibboleth'
+				url = 'https://build.shibboleth.net/nexus/content/repositories/releases/'
+			}
 		}
 	}
 

buildSrc/src/test/java/io/spring/gradle/convention/RepositoryConventionPluginTests.java

@@ -107,7 +107,7 @@ public void applyWhenIsReleaseWithForceLocalThenShouldIncludeReleaseAndLocalRepo
 		this.project.getPluginManager().apply(RepositoryConventionPlugin.class);
 
 		RepositoryHandler repositories = this.project.getRepositories();
-		assertThat(repositories).hasSize(4);
+		assertThat(repositories).hasSize(5);
 		assertThat((repositories.get(0)).getName()).isEqualTo("MavenLocal");
 	}
 
@@ -119,12 +119,12 @@ public void applyWhenIsReleaseWithForceMilestoneAndLocalThenShouldIncludeMilesto
 		this.project.getPluginManager().apply(RepositoryConventionPlugin.class);
 
 		RepositoryHandler repositories = this.project.getRepositories();
-		assertThat(repositories).hasSize(5);
+		assertThat(repositories).hasSize(6);
 		assertThat((repositories.get(0)).getName()).isEqualTo("MavenLocal");
 	}
 
 	private void assertSnapshotRepository(RepositoryHandler repositories) {
-		assertThat(repositories).extracting(ArtifactRepository::getName).hasSize(5);
+		assertThat(repositories).extracting(ArtifactRepository::getName).hasSize(6);
 		assertThat(((MavenArtifactRepository) repositories.get(0)).getUrl().toString())
 				.isEqualTo("https://repo.maven.apache.org/maven2/");
 		assertThat(((MavenArtifactRepository) repositories.get(1)).getUrl().toString())
@@ -136,7 +136,7 @@ private void assertSnapshotRepository(RepositoryHandler repositories) {
 	}
 
 	private void assertMilestoneRepository(RepositoryHandler repositories) {
-		assertThat(repositories).extracting(ArtifactRepository::getName).hasSize(4);
+		assertThat(repositories).extracting(ArtifactRepository::getName).hasSize(5);
 		assertThat(((MavenArtifactRepository) repositories.get(0)).getUrl().toString())
 				.isEqualTo("https://repo.maven.apache.org/maven2/");
 		assertThat(((MavenArtifactRepository) repositories.get(1)).getUrl().toString())
@@ -146,7 +146,7 @@ private void assertMilestoneRepository(RepositoryHandler repositories) {
 	}
 
 	private void assertReleaseRepository(RepositoryHandler repositories) {
-		assertThat(repositories).extracting(ArtifactRepository::getName).hasSize(3);
+		assertThat(repositories).extracting(ArtifactRepository::getName).hasSize(4);
 		assertThat(((MavenArtifactRepository) repositories.get(0)).getUrl().toString())
 				.isEqualTo("https://repo.maven.apache.org/maven2/");
 		assertThat(((MavenArtifactRepository) repositories.get(1)).getUrl().toString())