Rename StarlarkImportLookupFunction and friends

This renames "StarlarkImportLookup*" to "BzlLoad*", and also changes a number of uses of "import" to "load". This helps keep names to a more manageable length and is in line with modern Starlark terminology.

This is refactoring work toward adding a new kind of .bzl loading context, for Bazel-internal .bzl files.

Work toward #11437.

RELNOTES: None
PiperOrigin-RevId: 313240742
diff --git a/src/test/java/com/google/devtools/build/lib/skylark/StarlarkRuleClassFunctionsTest.java b/src/test/java/com/google/devtools/build/lib/skylark/StarlarkRuleClassFunctionsTest.java
index ec72f3f..089115e 100644
--- a/src/test/java/com/google/devtools/build/lib/skylark/StarlarkRuleClassFunctionsTest.java
+++ b/src/test/java/com/google/devtools/build/lib/skylark/StarlarkRuleClassFunctionsTest.java
@@ -49,7 +49,7 @@
 import com.google.devtools.build.lib.packages.StructImpl;
 import com.google.devtools.build.lib.packages.StructProvider;
 import com.google.devtools.build.lib.packages.Type;
-import com.google.devtools.build.lib.skyframe.StarlarkImportLookupFunction;
+import com.google.devtools.build.lib.skyframe.BzlLoadFunction;
 import com.google.devtools.build.lib.skylark.util.BazelEvaluationTestCase;
 import com.google.devtools.build.lib.syntax.ClassObject;
 import com.google.devtools.build.lib.syntax.Dict;
@@ -776,7 +776,7 @@
     if (!file.ok()) {
       throw new SyntaxError.Exception(file.errors());
     }
-    StarlarkImportLookupFunction.execAndExport(
+    BzlLoadFunction.execAndExport(
         file, FAKE_LABEL, ev.getEventHandler(), module, ev.getStarlarkThread());
   }