chore: clean up pom.xml variables (#4205)

This is a purely cosmetic change

Change-Id: Ia3750c137ae9f40c2e8124dbe5a807cbd706df6f

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Fixes #<issue_number_goes_here> ☕️

If you write sample code, please follow the [samples format](
https://togithub.com/GoogleCloudPlatform/java-docs-samples/blob/main/SAMPLE_FORMAT.md).

Author: igorbernstein2

bigtable-client-core-parent/bigtable-hbase/pom.xml

@@ -55,7 +55,7 @@ limitations under the License.
     <dependency>
       <groupId>${project.groupId}</groupId>
       <artifactId>bigtable-metrics-api</artifactId>
-      <version>${bigtable-client-core.version}</version>
+      <version>${bigtable-metrics-api.version}</version>
       <exclusions>
         <exclusion>
           <groupId>com.google.api</groupId>

bigtable-hbase-1.x-parent/bigtable-hbase-1.x-shaded/pom.xml

@@ -95,7 +95,7 @@ limitations under the License.
     <dependency>
       <groupId>com.google.cloud.bigtable</groupId>
       <artifactId>bigtable-metrics-api</artifactId>
-      <version>${bigtable-client-core.version}</version>
+      <version>${bigtable-metrics-api.version}</version>
       <exclusions>
         <exclusion>
           <groupId>com.google.api</groupId>

bigtable-hbase-1.x-parent/bigtable-hbase-1.x/pom.xml

@@ -61,7 +61,7 @@ limitations under the License.
     <dependency>
       <groupId>com.google.cloud.bigtable</groupId>
       <artifactId>bigtable-metrics-api</artifactId>
-      <version>${bigtable-client-core.version}</version>
+      <version>${bigtable-metrics-api.version}</version>
       <exclusions>
         <exclusion>
           <groupId>com.google.api</groupId>

bigtable-hbase-2.x-parent/bigtable-hbase-2.x-shaded/pom.xml

@@ -95,7 +95,7 @@ limitations under the License.
     <dependency>
       <groupId>com.google.cloud.bigtable</groupId>
       <artifactId>bigtable-metrics-api</artifactId>
-      <version>${bigtable-client-core.version}</version>
+      <version>${bigtable-metrics-api.version}</version>
     </dependency>
     <!-- Since opencensus-api is a transitive dep, we have to shade its impl as well.
     Otherwise the -api will be permanently severed from the impl and exporters -->

bigtable-hbase-2.x-parent/bigtable-hbase-2.x/pom.xml

@@ -76,7 +76,7 @@ limitations under the License.
     <dependency>
       <groupId>com.google.cloud.bigtable</groupId>
       <artifactId>bigtable-metrics-api</artifactId>
-      <version>${bigtable-client-core.version}</version>
+      <version>${bigtable-metrics-api.version}</version>
       <exclusions>
         <exclusion>
           <groupId>com.google.api</groupId>

pom.xml

@@ -58,7 +58,8 @@ limitations under the License.
     <!-- core dependency versions -->
     <bigtable.version>2.28.0</bigtable.version>
     <google-cloud-bigtable-emulator.version>0.165.0</google-cloud-bigtable-emulator.version>
-    <bigtable-client-core.version>1.29.2</bigtable-client-core.version>
+    <bigtable-metrics-api.version>1.29.2</bigtable-metrics-api.version>
+
     <!--  keeping at this version to align with hbase-->
     <slf4j.version>1.7.25</slf4j.version>
     <commons-logging.version>1.2</commons-logging.version>
@@ -83,13 +84,9 @@ limitations under the License.
     <beam.version>2.43.0</beam.version>
     <!-- referred from bigtable-beam-import and bigtable-emulator -->
     <guava.version>31.1-jre</guava.version>
-    <gcs-guava.version>29.0-jre</gcs-guava.version>
     <beam-slf4j.version>1.7.30</beam-slf4j.version>
     <opencensus.version>0.31.1</opencensus.version>
 
-    <!-- Benchmarks related dependencies -->
-    <jmh.version>1.36</jmh.version>
-
     <!-- Enable the ability to skip unit tests and only run integration tests,
          while still respecting global skipTests override. -->
     <skipTests>false</skipTests>
@@ -369,6 +366,7 @@ limitations under the License.
               <rules>
                 <bannedDependencies>
                   <excludes>
+                    <!-- Ban all known dependencies with CVEs -->
                     <exclude>commons-codec:commons-codec:[,1.15)</exclude>
                     <exclude>org.apache.commons:commons-compress:[,1.20)</exclude>
                     <!-- ban all log4j 2.x deps with CVEs -->