[libraries] align test setup (#29009)

* [libraries] move all the unit tests into test/unit

* [settings] remove empty test file

* [mongo-utils] remove test setup as there are no tests

* [libraries] ensure that all libraries with tests have test/setup.js

* [monorepo] remove test step from Cloud build for libraries without tests

GitOrigin-RevId: b9a0a8a3330db7d8646c7a272b03fbb8c5e44bc0

libraries/o-error/test/setup.js

@@ -0,0 +1 @@
+// no setup yet

libraries/o-error/test/unit/o-error-util.test.js

@@ -1,7 +1,7 @@
 const { expect } = require('chai')
 const { promisify } = require('node:util')
 
-const OError = require('..')
+const OError = require('../..')
 
 const {
   expectError,

libraries/o-error/test/unit/o-error.test.js

@@ -1,6 +1,6 @@
 const { expect } = require('chai')
 
-const OError = require('..')
+const OError = require('../..')
 const {
   expectError,
   expectFullStackWithoutStackFramesToEqual,

libraries/o-error/test/unit/support/index.js

@@ -1,6 +1,6 @@
 const { expect } = require('chai')
 
-const OError = require('../..')
+const OError = require('../../..')
 
 /**
  * @param {Error} e