Add Liquibase migrations. App now boots successfully.

src/main/resources/db/changelog/01-initial-schema.sql

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+-- Liquibase formatted SQL
+-- changeset dmigewant:1
+CREATE TABLE example_table (
+    id SERIAL PRIMARY KEY,
+    name VARCHAR(255) NOT NULL
+);

src/main/resources/db/changelog/db.changelog-master.yaml

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+databaseChangeLog:
+  - include:
+      file: 01-initial-schema.sql
+      relativeToChangelogFile: true