Harmonize build rule names to use hyphen instead of underscore

Change-Id: I31a4435d3f26edb6e9adbecdd88d8a9cedca8c0b

lib/slf4j/BUILD

diff --git a/lib/slf4j/BUILD b/lib/slf4j/BUILD
index 4a27aac..b619aaa 100644
--- a/lib/slf4j/BUILD
+++ b/lib/slf4j/BUILD
@@ -4,13 +4,13 @@
 
 java_library(
     name = "slf4j-api",
-    exports = ["@slf4j_api//jar"],
+    exports = ["@slf4j-api//jar"],
 )
 
 java_library(
     name = "slf4j-simple",
     runtime_deps = [
         ":slf4j-api",
-        "@slf4j_simple//jar",
+        "@slf4j-simple//jar",
     ],
 )