Open Replica read-only when possible (#3776)

* Open Replica read-only when possible

Specifically, when either
 - the command is read-only; or
 - the command requires GC (including recurrence updates) but GC is disabled by config

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

test/view_test.cpp

@@ -47,6 +47,7 @@ int TEST_NAME(int, char**) {
   UnitTest t(1);
   Context context;
   Context::setContext(&context);
+  context.tdb2.open_replica_in_memory();
 
   // Ensure environment has no influence.
   unsetenv("TASKDATA");