Preserve trailing whitespace in origin-tracked property values

Closes gh-13602

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/env/OriginTrackedPropertiesLoader.java

@@ -135,7 +135,7 @@ class OriginTrackedPropertiesLoader {
 			reader.read();
 		}
 		Origin origin = new TextResourceOrigin(this.resource, location);
-		return OriginTrackedValue.of(buffer.toString().trim(), origin);
+		return OriginTrackedValue.of(buffer.toString(), origin);
 	}
 
 	/**

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/env/OriginTrackedPropertiesLoaderTests.java

@@ -248,6 +248,12 @@ public class OriginTrackedPropertiesLoaderTests {
 		assertThat(getValue(value)).isEqualTo("æ×ÈÅÞßáñÀÿ");
 	}
 
+	@Test
+	public void getPropertyWithTrailingSpace() {
+		OriginTrackedValue value = this.properties.get("test-with-trailing-space");
+		assertThat(getValue(value)).isEqualTo("trailing ");
+	}
+
 	private Object getValue(OriginTrackedValue value) {
 		return (value != null ? value.getValue() : null);
 	}

spring-boot-project/spring-boot/src/test/resources/org/springframework/boot/env/test-properties.properties

@@ -40,3 +40,5 @@ test-multiline-immediate-bang=\
 
 #test ISO 8859-1
 test-iso8859-1-chars=ć×ČĹŢßáńŔ˙
+
+test-with-trailing-space= trailing