## Environment
**Liquibase Version**: org.liquibase:liquibase-core:jar:3.8.9

**Liquibase Integration & Version**: maven

**Database Vendor & Version**: postgres 11

**Operating System Type & Version**: ubuntu (wsl)

## Description
PrimaryKey constraint does not honor 'deferrable' and 'initiallyDeferred' settings so that created primary key is not 'deferred'

## Steps To Reproduce
Use script:

```
<databaseChangeLog xmlns="http://www.liquibase.org/xml/ns/dbchangelog"
                   xmlns:ext="http://www.liquibase.org/xml/ns/dbchangelog-ext"
                   xmlns:pro="http://www.liquibase.org/xml/ns/pro"
                   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                   xsi:schemaLocation="http://www.liquibase.org/xml/ns/dbchangelog-ext http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-ext.xsd http://www.liquibase.org/xml/ns/pro http://www.liquibase.org/xml/ns/pro/liquibase-pro-4.0.xsd http://www.liquibase.org/xml/ns/dbchangelog http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-4.0.xsd">
    <changeSet author="author" id="some-id">  
        <createTable tableName="abc">
            <column name="id" type="INTEGER">
                <constraints nullable="false" primaryKey="true" primaryKeyName="abc_PK" deferrable="true" initiallyDeferred="true"/>
            </column>
        </createTable>
    </changeSet>
</databaseChangeLog>
```

## Actual Behavior
2020-12-18 09:01:19.936 [main] INFO  liquibase.executor.jvm.JdbcExecutor - CREATE TABLE public.abc (id INTEGER NOT NULL, CONSTRAINT "abc_PK" PRIMARY KEY (id))

## Expected/Desired Behavior
PRIMARY KEY is created with _deferrable initially deferred_


buffer.append(" PRIMARY KEY (");
                buffer.append(database.escapeColumnNameList(StringUtil.join(statement.getPrimaryKeyConstraint().getColumns(), ", ")));
                buffer.append(")");
                
                if (((database instanceof OracleDatabase) || (database instanceof PostgresDatabase)) && (statement
                        .getPrimaryKeyConstraint().getTablespace() != null)) {
                    buffer.append(" USING INDEX TABLESPACE ");
                    buffer.append(statement.getPrimaryKeyConstraint().getTablespace());
                }
                buffer.append(!statement.getPrimaryKeyConstraint().shouldValidatePrimaryKey() ? " ENABLE NOVALIDATE " : "");
                buffer.append(",");
            }
        }
        for (ForeignKeyConstraint fkConstraint : statement.getForeignKeyConstraints()) {
            if (!(database instanceof InformixDatabase)) {
                buffer.append(" CONSTRAINT ");
                buffer.append(database.escapeConstraintName(fkConstraint.getForeignKeyName()));
            }
            String referencesString = fkConstraint.getReferences();
            buffer.append(" FOREIGN KEY (")
                    .append(database.escapeColumnName(statement.getCatalogName(), statement.getSchemaName(), statement.getTableName(), fkConstraint.getColumn()))
                    .append(") REFERENCES ");
            if (referencesString != null) {
                if (!referencesString.contains(".") && (database.getDefaultSchemaName() != null) && database
                        .getOutputDefaultSchema()) {
                    referencesString = database.escapeObjectName(database.getDefaultSchemaName(), Schema.class) + "." + referencesString;
                }
                buffer.append(referencesString);
            } else {
                buffer.append(database.escapeObjectName(fkConstraint.getReferencedTableCatalogName(), fkConstraint.getReferencedTableSchemaName(), fkConstraint.getReferencedTableName(), Table.class))