Bigtable: fix emulator publishing

Currently the emulator can't be used because it's parent pom is not published.
THis PR removes the parent and copies the relevant bits into the emulator's pom
Fixes googleapis#4187

google-cloud-testing/google-cloud-bigtable-emulator/pom.xml

@@ -2,13 +2,9 @@
 <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">
-  <parent>
-    <artifactId>google-cloud-testing</artifactId>
-    <groupId>com.google.cloud</groupId>
-    <version>0.72.1-alpha-SNAPSHOT</version><!-- {x-version-update:google-cloud-testing:current} -->
-  </parent>
   <modelVersion>4.0.0</modelVersion>
 
+  <groupId>com.google.cloud</groupId>
   <artifactId>google-cloud-bigtable-emulator</artifactId>
   <version>0.72.1-alpha-SNAPSHOT</version><!-- {x-version-update:google-cloud-bigtable-emulator:current} -->
 
@@ -25,6 +21,18 @@
 
   <build>
     <plugins>
+      <plugin>
+        <artifactId>maven-compiler-plugin</artifactId>
+        <version>3.7.0</version>
+        <configuration>
+          <source>1.7</source>
+          <target>1.7</target>
+          <encoding>UTF-8</encoding>
+          <compilerArgument>-Xlint:unchecked</compilerArgument>
+          <compilerArgument>-Xlint:deprecation</compilerArgument>
+          <showDeprecation>true</showDeprecation>
+        </configuration>
+      </plugin>
       <plugin>
         <groupId>com.google.cloud</groupId>
         <artifactId>google-cloud-gcloud-maven-plugin</artifactId>
@@ -66,6 +74,18 @@
     </plugins>
   </build>
 
+  <dependencyManagement>
+    <dependencies>
+      <dependency>
+        <groupId>com.google.cloud</groupId>
+        <artifactId>google-cloud-bom</artifactId>
+        <version>0.72.1-alpha-SNAPSHOT</version><!-- {x-version-update:google-cloud-bom:current} -->
+        <type>pom</type>
+        <scope>import</scope>
+      </dependency>
+    </dependencies>
+  </dependencyManagement>
+
   <dependencies>
     <!-- grpc deps are provided by the client -->
     <dependency>
@@ -91,13 +111,15 @@
     <dependency>
       <groupId>junit</groupId>
       <artifactId>junit</artifactId>
+      <version>4.12</version>
       <scope>compile</scope>
       <optional>true</optional>
     </dependency>
 
     <dependency>
       <groupId>com.google.truth</groupId>
       <artifactId>truth</artifactId>
+      <version>0.30</version>
       <scope>test</scope>
     </dependency>