mvn install stopped working within the last 24 hours.
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[INFO] Scanning for projects...
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[INFO] Reactor Build Order:
[INFO]
[INFO] Jenkins main module [pom]
[INFO] Jenkins cli [jar]
[INFO] Jenkins core [jar]
[INFO] Jenkins war [war]
[INFO] Jenkins core tests POM [pom]
[INFO] Tests for Jenkins core [jar]
[INFO] JDK8-only tests for Jenkins core [jar]
[INFO]
[INFO] -----------------< org.jenkins-ci.main:jenkins-parent >-----------------
[INFO] Building Jenkins main module 2.161-SNAPSHOT [1/7]
[INFO] --------------------------------[ pom ]---------------------------------
[INFO] ------------------------------------------------------------------------
[INFO] Reactor Summary:
[INFO]
[INFO] Jenkins main module 2.161-SNAPSHOT ................. FAILURE [ 0.110 s]
[INFO] Jenkins cli ........................................ SKIPPED
[INFO] Jenkins core ....................................... SKIPPED
[INFO] Jenkins war ........................................ SKIPPED
[INFO] Jenkins core tests POM ............................. SKIPPED
[INFO] Tests for Jenkins core ............................. SKIPPED
[INFO] JDK8-only tests for Jenkins core 2.161-SNAPSHOT .... SKIPPED
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 4.329 s
[INFO] Finished at: 2019-01-20T09:43:57-08:00
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal on project jenkins-parent: Could not resolve dependencies for project org.jenkins-ci.main:jenkins-parent:pom:2.161-SNAPSHOT: Failed to collect dependencies at javax.servlet:servlet-api:jar:[0,0]: No versions available for javax.servlet:servlet-api:jar:[0,0] within specified range -> [Help 1]
[ERROR]
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR]
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1]
http://cwiki.apache.org/confluence/display/MAVEN/DependencyResolutionException