Add dotenv-rails gem to fix environment variable error for db setup (#334)

* Add dotenv-rails gem to fix environment variable error for db setup

* Add environment variables

* Add default database values to environment variables

.env.example

@@ -12,4 +12,9 @@ SMTP_ADDRESS=
 SMTP_PORT=465
 SMTP_USERNAME=
 SMTP_PASSWORD=
-TLS=true
+TLS=true
+
+# Database Configuration
+DB_HOST=localhost
+POSTGRES_PASSWORD=postgres
+POSTGRES_USER=postgres

Gemfile

@@ -34,6 +34,7 @@ group :development, :test do
   gem "brakeman", require: false
   gem "rubocop-rails-omakase", require: false
   gem "dotenv"
+  gem "dotenv-rails"
   gem "letter_opener"
   gem "i18n-tasks"
 end

Gemfile.lock

@@ -143,6 +143,9 @@ GEM
       irb (~> 1.10)
       reline (>= 0.3.8)
     dotenv (2.8.1)
+    dotenv-rails (2.8.1)
+      dotenv (= 2.8.1)
+      railties (>= 3.2)
     drb (2.2.0)
       ruby2_keywords
     erubi (1.12.0)
@@ -385,6 +388,7 @@ DEPENDENCIES
   capybara
   debug
   dotenv
+  dotenv-rails
   hotwire-livereload
   i18n-tasks
   importmap-rails