chore: release 2.0.0

[release-please]

🤖 I have created a release *beep* *boop*

2.0.0 (2021-03-24)

⚠ BREAKING CHANGES

• upgrade to Java 8 and JDBC 4.2 (feat!: upgrade to Java 8 and JDBC 4.2 #397)

Features

• upgrade to Java 8 and JDBC 4.2 (#397) (7eedfbc)

Performance Improvements

• use PLAN mode to get result metadata (#388) (8c7b665)

Documentation

• add reference to jar-with-dependencies in readme (#404) (12c3235), closes #399

Dependencies

• update dependency com.google.cloud:google-cloud-spanner-bom to v5.1.0 (#393) (9b36a54)
• update dependency com.google.cloud:google-cloud-spanner-bom to v5.2.0 (#398) (8482652)
• update dependency com.google.cloud:google-cloud-spanner-bom to v6 (#403) (3e0fbd1)

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[codecov]

Codecov Report

Merging #407 (5b6338a) into master (ff53e29) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##             master     #407   +/-   ##
=========================================
  Coverage     72.70%   72.70%           
  Complexity     1162     1162           
=========================================
  Files            24       24           
  Lines          3583     3583           
  Branches        533      533           
=========================================
  Hits           2605     2605           
  Misses          757      757           
  Partials        221      221           

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[yoshi-automation]

🤖 Release is at https://github.com/googleapis/java-spanner-jdbc/releases/tag/v2.0.0 🌻

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