Assign oncalls to semr and decl HHVM extensions

Summary:
- Set semr extension oncall to "web_infra" (previously NO_ONCALL_YET)
- Set decl extension oncall to "sandbox_infra" (previously NO_ONCALL_YET),
  matching its BUCK file oncall annotation

Reviewed By: rikeoka, jtwarren

Differential Revision: D95139645

fbshipit-source-id: ba1465001539284e538c5510d04894fa98ff79f4

Author: Anicet Dushime Wa Mungu

hphp/runtime/ext/decl/ext_decl.cpp

@@ -1160,7 +1160,7 @@ HHVM_METHOD(FileDecls, getAttribute, const String& kls, const String& name) {
 // Extension
 
 struct DeclExtension final : Extension {
-  DeclExtension() : Extension("decl", "0.1", NO_ONCALL_YET) {}
+  DeclExtension() : Extension("decl", "0.1", "sandbox_infra") {}
 
   const DependencySet getDeps() const override {
     // ensure ext_facts initializes and loads first.