* Add github action for testing oci8 Oracle.
* Fix CommandTest::testQueryCache.
* Fix tests CommandTest::testBindParamsNonWhere.
* Fix test CommandTest::testInsert.
* Fix test CommanTest::testInsertExpression.
* Fix test CommandTest::testInsertSelectAlias.
* Fix test CommandTest::testBindParamValue.
* Fix tests CommandTest::testBatchInsertDataTypesLocale.
* Fix test CommandTest::testNoTablenameReplacement.
* Fix test CommandTest::testCreateTable.
* Fix test CommandTest::testsInsertQueryAsColumnValue.
* Fix tests CommandTest::testAlterTable.
* Fix test CommandTest::testCreateView.
* Fix test CommandTest::testTransaction.
* Fix test ConnectionTest::testTransactionShortcutCorrect.
* Fix test ConnectionTest::testTransactionShortcutCustom.
* Fix test ConnectionTest::testEnableQueryLog.
* Fix test QueryBuilder::testAddDropDefaultValue.
* Fix test QueryTest::testUnion.
* Fix test QueryTest::testExpressionInFrom.
* Fix test SchemaTest::testFindUniqueIndexes.
* Fix test QueryBuilderTest::testGetColumnType.
* Fix test ActiveRecordTest::testFind.
* Fix test ExistValidatorTest::testExpresionInAttributeColumnName.
* Fix test UniqueValidatorTest::testExpressionInAttributeColumnName.
* Fix ActiveRecordTest testCastValues(), testDefaultValues.
* Fix test UniqueValidatorTest::testValidateAttributeDefault.
* Fix test UniqueValidatorTest::testValidateEmptyAttributeInStringField.
* Fix test UniqueValidatorTest::testValidateEmptyAttributeInIntField.
* Fix test ActiveRecordTest::testBit.
* Fix test ActiveRecordTest::testBooleanAttribute.
* Fix test ActiveRecordTest::testJoinWithAlias.
* Fix test SchemaTest::testColumnSchema.
* Fix test CommandTest:: testBatchInsertSQL.
* Skip CommandTest::testColumnCase.
* Fix test ConnectionTest::testQuoteValue.
* Should be fixed tests conditionsProvider in QueryBuilderTest.
* Fix ActiveRecordTest.php
* Fix test UniqueValidatorTest.
* Fix test QueryBuilderTest::testUpsert.
* Skip SchemaTest::testCompositeFK.
PHPUnit must get the data that will be passed to the tests, before executing them. That's why you can't prevent the dataProvider to be executed using `$this->markTestSkipped()` inside a test. Instead, you must use a skipping inside data provider when the test cannot be executed.
Now Oracle tests are skipped without fails when Oracle isn't installed:
```
$ vendor/bin/phpunit --filter=BuildLikeCondition --group=oci --verbose
...
There was 1 skipped test:
1) yiiunit\framework\db\oci\QueryBuilderTest::testBuildLikeCondition
Test for yiiunit\framework\db\oci\QueryBuilderTest::testBuildLikeCondition skipped by data provider
Could not execute Connection::quoteValue() method: Connection::dsn cannot be empty.
```
- changed test class naming for easier copying and searching of classes
- made base tests abstract and made MySQL an equal citisen in the test
hierarchie
- added missing db specific test classes