[Geoip+ci] Fix flaky release check in ci (#36118)

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Commit Message:
Additional Description:
Risk Level:
Testing:
Docs Changes:
Release Notes:
Platform Specific Features:
[Optional Runtime guard:]
Partially Fixes #35829
[Optional Fixes commit #PR or SHA]
[Optional Deprecated:]
[Optional [API
Considerations](https://github.com/envoyproxy/envoy/blob/main/api/review_checklist.md):]

Signed-off-by: Kateryna Nezdolii <kateryna.nezdolii@gmail.com>

test/extensions/geoip_providers/maxmind/geoip_provider_test.cc

@@ -94,7 +94,6 @@ class GeoipProviderTestBase {
         Registry::FactoryRegistry<Geolocation::GeoipProviderFactory>::getFactory(
             "envoy.geoip_providers.maxmind"));
     ASSERT(provider_factory_);
-    on_changed_cbs_.reserve(1);
   }
 
   ~GeoipProviderTestBase() {
@@ -116,6 +115,7 @@ class GeoipProviderTestBase {
                                                           Filesystem::Watcher::OnChangedCb cb) {
                 {
                   absl::WriterMutexLock lock(&mutex_);
+                  on_changed_cbs_.reserve(1);
                   on_changed_cbs_.emplace_back(std::move(cb));
                 }
                 if (conditional.has_value()) {