chore: release 5.3.0

[release-please]

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

5.3.0 (2020-09-04)

Features

• accept gaxOptions in Database and Session #delete() (#1206) (2444e8e)
• add resource header prefix (#1196) (99744b6)
• return full nextQuery object in paginated calls (#1199) (445015f)
• set metadata during getBackups and getMetadata calls (#1198) (aa500a5)
• spanner NUMERIC support (#1163) (4724ba3)
• Spanner numeric type, add Node 8 tests (#1189) (c2bc40e)

Bug Fixes

• Database not found could be returned after create() (#1220) (1fddbb9), closes #1219 #1219
• batch transaction should use a session from the pool (#1207) (0708baa), closes #1200
• handle potential errors when creating stream (#1208) (fcf35f5), closes #1078
• retry PDML on Aborted and Internal errors (#1205) (2b97bac), closes #1197
• update minimum gax version to 2.7.0 (#1213) (224de8f), closes #1209
• spanner: update UpdateBackup to be retryable (#1194) (e53a247)
• typeo in nodejs .gitattribute (#1178) (439d5af)

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This PR was generated with Release Please.

[codecov]

Codecov Report

Merging #1193 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #1193   +/-   ##
=======================================
  Coverage   98.59%   98.59%           
=======================================
  Files          23       23           
  Lines       21350    21350           
  Branches     1248     1248           
=======================================
  Hits        21050    21050           
  Misses        297      297           
  Partials        3        3           

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[yoshi-automation]

Release is at https://github.com/googleapis/nodejs-spanner/releases/tag/v5.3.0

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[release-tool-publish-reporter]

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