Use let instead of var, fix failing test.

__tests__/config.test.ts

@@ -2,7 +2,7 @@ import { expect, test } from '@jest/globals'
 import { readConfigFile } from '../src/config'
 
 test('reads the config file', async () => {
-    var options = readConfigFile("./__tests__/fixtures/config-allow-sample.yml")
+    let options = readConfigFile("./__tests__/fixtures/config-allow-sample.yml")
     expect(options.fail_on_severity).toEqual('critical')
     expect(options.allow_licenses).toEqual(['BSD', 'GPL 2'])
 })
@@ -16,7 +16,7 @@ test('the default config path handles .yml and .yaml', async () => {
 })
 
 test('returns a default config when the config file was not found', async () => {
-    var options = readConfigFile("fixtures/i-dont-exist")
-    expect(options.fail_on_severity).toEqual('all')
+    let options = readConfigFile("fixtures/i-dont-exist")
+    expect(options.fail_on_severity).toEqual('low')
     expect(options.allow_licenses).toEqual(['all'])
-})
+})

__tests__/filter.test.ts

@@ -47,8 +47,8 @@ let rubyChange: Change = {
 }
 
 test('it properly filters changes by severity', async () => {
-    let changes: Changes = [npmChange, rubyChange]
-    const expectedChanges: Changes = [npmChange]
+    let changes = [npmChange, rubyChange]
+    const expectedChanges = [npmChange]
     changes = filterChangesBySeverity('high', changes)
     expect(changes).toEqual(expectedChanges)
 })