IGNITE-15440 Fix some WARNINGS in Maven build (#312)

diff --git a/assembly/assembly.xml b/assembly/assembly.xml
index 8a8ed05..4987f17 100644
--- a/assembly/assembly.xml
+++ b/assembly/assembly.xml
@@ -54,7 +54,7 @@
 
         <file>
             <source>examples/pom-standalone.xml</source>
-            <outputDirectory>/examples</outputDirectory>
+            <outputDirectory>./examples</outputDirectory>
             <destName>pom.xml</destName>
         </file>
     </files>
@@ -62,7 +62,7 @@
     <fileSets>
         <fileSet>
             <directory>examples</directory>
-            <outputDirectory>/examples</outputDirectory>
+            <outputDirectory>./examples</outputDirectory>
             <includes>
                 <include>config/**</include>
                 <include>src/**</include>
diff --git a/modules/calcite/pom.xml b/modules/calcite/pom.xml
index 6e84990..c1005e7 100644
--- a/modules/calcite/pom.xml
+++ b/modules/calcite/pom.xml
@@ -17,9 +17,6 @@
   limitations under the License.
 -->
 
-<!--
-    POM file.
--->
 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
     <modelVersion>4.0.0</modelVersion>
diff --git a/parent/pom.xml b/parent/pom.xml
index 6787898..f008a23 100644
--- a/parent/pom.xml
+++ b/parent/pom.xml
@@ -15,9 +15,6 @@
   limitations under the License.
 -->
 
-<!--
-    POM file.
--->
 <project
         xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"