chore: migrate to gapic-libraries-bom (#1914)

Change-Id: I14ac3a23adb0d137d72ac620884c00aee7095f70

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- [ ] Make sure to open an issue as a [bug/issue](https://togithub.com/googleapis/java-bigtable/issues/new/choose) before writing your code!  That way we can discuss the change, evaluate designs, and agree on the general idea
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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).

google-cloud-bigtable-deps-bom/pom.xml

@@ -65,22 +65,15 @@
     <dependencies>
       <dependency>
         <groupId>com.google.cloud</groupId>
-        <artifactId>google-cloud-shared-dependencies</artifactId>
-        <version>3.15.0</version>
+        <artifactId>gapic-libraries-bom</artifactId>
+        <version>1.18.0</version>
         <type>pom</type>
         <scope>import</scope>
       </dependency>
       <dependency>
         <groupId>com.google.cloud</groupId>
-        <artifactId>google-cloud-monitoring-bom</artifactId>
-        <version>3.25.0</version>
-        <exclusions>
-          <exclusion>
-            <!-- using the perfmark version in opencensus -->
-            <groupId>io.perfmark</groupId>
-            <artifactId>perfmark-api</artifactId>
-          </exclusion>
-        </exclusions>
+        <artifactId>google-cloud-shared-dependencies</artifactId>
+        <version>3.15.0</version>
         <type>pom</type>
         <scope>import</scope>
       </dependency>