revert too much sync :-)

We want to ignore some warnings from Spotbugs.

Author: kfriedberger

build/SpotBugs.exclude.xml

@@ -9,6 +9,12 @@ SPDX-License-Identifier: Apache-2.0
 -->
 
 <FindBugsFilter>
+    <!-- Exceptions from constructors are not really a problem,
+         e.g., we inject configuration options and want to fail fast. -->
+    <Match><Bug pattern="CT_CONSTRUCTOR_THROW"/></Match>
+    <!-- These checks are too pessimistic: https://github.com/spotbugs/spotbugs/issues/1601 -->
+    <Match><Bug pattern="EI_EXPOSE_REP"/></Match>
+    <Match><Bug pattern="EI_EXPOSE_REP2"/></Match>
     <!-- SpotBugs does not support @org.checkerframework.checker.nullness.qual.Nullable
          (cf. https://github.com/spotbugs/spotbugs/issues/643) -->
     <Match><Bug code="NP,RCN"/></Match>