Fix incorrect LogManager accessor used by LOG4J2-2940

The `getContext()` accessor with no args has been used as a fallback
for Log4jLoggerFactory slf4j implementations for a while, but it's
much more likely to be used now that LOG4J2-2940 is resolved.
Without the `false` argument, the first slf4j LoggerFactory.getLogger
call will not cause log4j to initialize itself.
diff --git a/log4j-slf4j-impl/src/main/java/org/apache/logging/slf4j/Log4jLoggerFactory.java b/log4j-slf4j-impl/src/main/java/org/apache/logging/slf4j/Log4jLoggerFactory.java
index ce71630..e5b0e58 100644
--- a/log4j-slf4j-impl/src/main/java/org/apache/logging/slf4j/Log4jLoggerFactory.java
+++ b/log4j-slf4j-impl/src/main/java/org/apache/logging/slf4j/Log4jLoggerFactory.java
@@ -45,7 +45,7 @@
                 ? StackLocatorUtil.getCallerClass(FQCN, PACKAGE, 1)
                 : null;
         return anchor == null
-                ? LogManager.getContext()
+                ? LogManager.getContext(false)
                 : getContext(anchor);
     }
 
diff --git a/log4j-slf4j18-impl/src/main/java/org/apache/logging/slf4j/Log4jLoggerFactory.java b/log4j-slf4j18-impl/src/main/java/org/apache/logging/slf4j/Log4jLoggerFactory.java
index a1daa86..bb2a2d8 100644
--- a/log4j-slf4j18-impl/src/main/java/org/apache/logging/slf4j/Log4jLoggerFactory.java
+++ b/log4j-slf4j18-impl/src/main/java/org/apache/logging/slf4j/Log4jLoggerFactory.java
@@ -51,7 +51,7 @@
                 ? StackLocatorUtil.getCallerClass(FQCN, PACKAGE, 1)
                 : null;
         return anchor == null
-                ? LogManager.getContext()
+                ? LogManager.getContext(false)
                 : getContext(anchor);
     }